genetics of hypogonadotropic hypogonadism lawrence c. layman, m.d. professor chief, section of...
Post on 19-Dec-2015
220 views
TRANSCRIPT
![Page 1: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/1.jpg)
Genetics of HypogonadotropicHypogonadism
Lawrence C. Layman, M.D.ProfessorChief, Section of Reproductive Endocrinology,
Infertility, & GeneticsDepartment of Obstetrics & GynecologyNeurobiology ProgramThe Institute of Molecular Medicine & GeneticsThe Medical College of GeorgiaAugusta, GA
![Page 2: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/2.jpg)
Genetics of IHHGenetics of IHH
1. Normal pubertal milestones2. Idiopathic hypogonadotropic
hypogonadism (IHH)3. Mutations/phenotype
A.Hypothalamic:KAL1, NROBI, FGFR1, LEP, LEPR
B. Pituitary: GNRHR, PROP1, HESX1, FSHB, LHB
![Page 3: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/3.jpg)
LHFSH
GnRH
HYPOTHALAMUS
PITUITARY
GONAD
Steroids Gametes
Normal H-P-G AxisNormal H-P-G Axis
![Page 4: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/4.jpg)
Normal Pubertal Milestones
Females: Breasts: age 9-11Pubic hair: 8-9Growth spurt: 12Menses: age 12
Males:Testes: age 10-11Pubic hair: 10-11Penile growth: 13Growth spurt: 14
![Page 5: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/5.jpg)
Delayed Puberty
1) Females:
No breast development: age 13No menses: age 15
2) Males:
No testes development: age 14
![Page 6: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/6.jpg)
Hypogonadism:Low sex steroidsNo pubertal development
Obtain serum gonadotropins(LH and FSH)
Clinical Evaluation
![Page 7: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/7.jpg)
LHFSH
GnRH
HYPO
PIT
GONAD
Steroids Gametes
H-P-G Axis DysfunctionH-P-G Axis Dysfunction
HypergonadotropicHypogonadism
• High FSH & LH• Low sex steroids
![Page 8: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/8.jpg)
• Irreversible, delayed puberty Females: age 17 AmenorrheaMales: age 18 Low T (< 100ng/dL)
• Low FSH, LH • No CNS lesion• Normal prolactin, thyroid, adrenal function
Idiopathic HypogonadotropicHypogonadism (IHH)
![Page 9: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/9.jpg)
LHFSH
GnRH
HYPO
PIT
GONAD
Steroids Gametes
HypogonadotropicHypogonadism
H-P-G Axis DysfunctionH-P-G Axis Dysfunction
• Low FSH & LH• Low sex steroids
![Page 10: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/10.jpg)
Gonadotropins in IHH
• Gonadotropin responses to exogenous GnRH variable
• LH Pulsatility Patterns—serial samples(every 10-20 minutes)
1) Apulsatile2) Decreased frequency3) Decreased amplitude4) Nocturnal prepubertal pattern
![Page 11: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/11.jpg)
Prospects for Fertility
Hypogonadotropic Hypogonadism:
• Induce secondary sex characteristics with steroids (estrogen or testosterone)• Hypothalamic or pituitary• If pituitary failure, replace pituitary
hormones • Supply missing gonadotropins or GnRH• Good prognosis depending upon age
(20%/cycle)
![Page 12: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/12.jpg)
OMIM Entries with IHH (>40)215470 Chorioretinal dystrophy, spinocerebellar
ataxia & HH253320 Multicore myopathy with mental retardation,
short stature, & HH212840 Cerebellar ataxia & HH176270 Prader-Willi syndrome176270 Fertile eunich syndrome235200 Hemochromatosis (HFE)602390 Hemochromatosis type (HFE2)157900 Moebius syndrome209900 Bardet-Biedl syndrome (BBS1-6)
![Page 13: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/13.jpg)
GNRHR
NROB1LEP/LEPR
LHFSH
HYPOTHALAMUS
PITUITARY
GONAD
SteroidsGametes
GnRH
LHBFSHB
PROP1
HESX1
FGFR1
KAL1
![Page 14: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/14.jpg)
GNRH1 Gene
• Pivotal gene in reproduction
• Expressed in: 1. Hypothalamus2. Pituitary3. Placenta4. Ovary5. Breast
• Deficiency: hypogonadotropic hypogonadism
![Page 15: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/15.jpg)
IHH
1. Hypogonadal mouse: Gnrh1 gene deletion
2. Human IHH: no GNRH1 genemutations
Mason et al. Science 1986;234:1372.
Weiss et al. J Clin Endocrinol Metab 1989;69:299.Layman et al. Fertil Steril 1992;57:42.Nakayama et al. J Clin Endocrinol Metab 1990;70:1233.
![Page 16: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/16.jpg)
Kallmann syndrome• IHH• Anosmia• Neurologic abnormalities:
synkinesiavisual abnormalities
• Renal anomalies• Midfacial defects
X-linked recessive: males
![Page 17: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/17.jpg)
Kallmann syndrome
• GnRH & olfactory neurons migrate from olfactory placode to hypothalamus
• KAL1 gene: protein directs migration, so if mutations 1. Anosmia
2. GnRH deficiency
Franco et al. Nat 1991;353:529.Legouis et al. Cell 1991;67:423.
![Page 18: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/18.jpg)
Kallmann Syndrome• KAL1 gene mutations in ~50% X-linked
families• Half of males with KAL1 mutations have
unilateral renal agenesis
• About 5% or less of unselected K.S. males have KAL1 gene mutations
(Hardelin et al. Hum Mol Genet 1993;2:373)
Bick et al. N Eng J Med 1992;326:1752.Georgopoulos et al. J CEM 1997;82:213.Layman et al. J Soc Gynecol Invest 1998
![Page 19: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/19.jpg)
Olfactory bulb AnosmiaCerebellum Nystagmus
AtaxiaSpinal cord (cort/spinal) SynkinesiaOculomotor nucleus Eye movement
abnormalitiesRetina Visual defectsMeso- & meta- nephros Renal agenesisFacial mesenchyme Cleft palateCartilage & Limb bud Club foot
Expression PhenotypeKallmann syndromeKallmann syndrome
![Page 20: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/20.jpg)
Prevalence of KAL1 Mutations
Oliveira et al. JCEM 2001;86:1532-8.
KAL1 mutations
1) Familial KS: 3/21 (14%)2) Sporadic KS: 4/38 (11%)3) Normosmic IHH: 0/42
Total KS: 7/59 (12%)Total IHH patients: 7/101 (7%)
![Page 21: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/21.jpg)
Kallmann syndrome• KAL1 on pseudoautosomal Xp• Inactive pseudogene on Yq• Encodes anosmin-1, a protein with
neural cell adhesion properties
• Orthologs in chicks, zebrafish, C.elegans, Drosophila
• Not cloned in murine species yet, buthuman Abs detect its presence
Franco et al. Nat 1991;353:529.Legouis et al. Cell 1991;67:423.
MacColl et al. Neuron 2002:34:675-8.
![Page 22: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/22.jpg)
(Ruglari et al. Devel 2002;129:1283-94.)
Bulow et al PNAS 2002;99:6346-51.
Anosmin-1• C elegans ortholog (CeKal1) cloned• Required for ventral enclosure & male
ray (tail) formation during embryogenesis• Modulates branching of neurites• Human KAL1 cDNA can compensate for loss
of worm CeKal1 indicating function conserved
• Secreted molecule that binds via heparan sulfateproteoglycan to its receptor to induce axonbranching and misrouting
![Page 23: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/23.jpg)
Kallmann syndrome
1) Absent LOT branches causes anosmia2) Lack of GnRH neurons to forebrain causes
IHH3) May be anosmia also because of lack of
primary contacts between olfactory axons& OB anlage
Hypothesis: anosmin-1 in OB area exertsattractive effect of olfactory receptor neuronsto create contact
Soussi-Yanicostas et al. Cell 2002;109:217-28.
![Page 24: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/24.jpg)
Adrenal Hypoplasia Congenita (AHC)Hypogonadotropic Hypogonadism (HH)
• Adrenal failure in infancy to age 10• If survive, have delayed puberty (HH)• X-linked recessive• NROB1 gene (formerly DAX1) mutations,
steroid receptor, cause both AHC/HH• Adrenal, hypothalamic, pituitary develop• DSS region on Xp
Zanaria et al. Nat 1994;372:635.Muscatelli et al. Nat 1994;372:672.
![Page 25: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/25.jpg)
NROB1 (DAX1) Heterogeneity
• Normal response to GnRH (suggesting hypothalamic defect)
• Minimal LH response during GnRHpriming (suggesting pituitary)
Del1219nt & Gly329Glu
Habiby et al. JCI 1996;98:1055.
GGAT duplication codon 418• Normal FAS, no response to GnRH
(suggesting pituitary)
![Page 26: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/26.jpg)
NROB1 (DAX1) in IHH
• 106 IHH males (85 sporadic; 21 familial)• DNA sequencing of the coding region
No mutations
ConclusionConclusion: NROB1 mutations uncommonin IHH patients without AHC
Achermann et al. JCEM 1999;84:4497-4500.
![Page 27: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/27.jpg)
NROB1 (DAX1) in Females
• Mutation in female with HH (no AHC), whohad with skewed X-inactivation
• Variabile expression within the family (bothmales had HH/AHC)Merke et al. NEJM 1999;340:1248-1252.
• Female with HH & missense mutation? in NH2ASHG 2002 meeting 10/02
• Conditional KO: not ovarian determinant, butinstead important for spermatogenesis
Yu et al. Nat Genet 1998;20:353-357.
![Page 28: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/28.jpg)
Leptin DeficiencyLeptin Deficiency Leptin deficient ob/ob mouse:
• Obesity• Hyperinsulinemia• Infertility (20 to HH)• Hypothermia• Cold intolerance• Hypercortisolemia
Zhang et al. Nat 1994;372:425-432.
![Page 29: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/29.jpg)
Human Leptin DeficiencyHuman Leptin Deficiency
• LEP deficiency causes early onset obesity(Montague et al. Nat 1997;387:903-908)
• Causes obesity & HH(Strobel et al. Nat Genet 1998;18:214-215.)
• Normally: + correlation of BMI & leptin
• Leptin deficiency rare in obesity
![Page 30: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/30.jpg)
LEP Gene Mutations & HH
Obese Male:• BMI = 55.8 kg/m2• Low serum leptin (0.9ng/mL)
• C T (Arg105Trp)•Autosomal recessive• 2 sibs with similar phenotype• Mutant not secreted from cell
Strobel et al. Nat Genet 1998;18:214-215.
![Page 31: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/31.jpg)
Clement et al. Nat 1998;392:398-401
Leptin Receptor Gene Mutation
• Obesity and HH• Homozygous G to A in splice donor site
(exon skipping exon 16)• Protein truncated (lack transmembrane
intracellular domains)
![Page 32: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/32.jpg)
FGFR1 Mutations
Dode et al. Nat Genet 2003;33:463-465.
• Autosomal dominant Kallmann syndrome(IHH & anosmia)
• Loss of function mutations in fibroblast growth factor receptor 1 (FGFR1)
• Also termed KAL2• Gain of function mutations cause cranio-
synostosis (Pfeiffer syndrome) & craniofacial-skeletal dysplasia (Jackson-Weiss)syndrome
![Page 33: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/33.jpg)
FGFR1 Mutations
Dode et al. Nat Genet 2003;33:463-465.
• Identified 10-11Mb region on 8p11.2-p12 via2 patients with contiguous gene deletionsyndromes, who also had KS
• Region had three genes—FGFR1 candidate• None of 43 patients had deletions (Southern)• 12/129 (9.3%) unrelated patients with KS
(91 males; 38 females) had mutations• Reduced penetrance & variable expressivity• Some patients with cleft palate/lip,
dentogenesis, synkinesis
![Page 34: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/34.jpg)
FGFR1 & KAL1 Relationship
Dode et al. Nat Genet 2003;33:463-465.
• Could anosmin-1 (KAL1 protein) be the ligandfor FGFR1?
• FGF interacts with the FGFR1 and heparansulfate proteoglycans (HSPGs)—necessaryfor receptor dimerization & autophosphorylation
• Anosmin-1 binds to HSPGs
• KAL1 expressed in olfactory bulbs & Fgfr1 isexpressed in rostral forebrain & requiredfor olfactory bulb evagination in mouse
![Page 35: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/35.jpg)
GNRHR Gene MutationsGNRHR Gene Mutations
Partial IHH
Complete IHH
• Low LH, low FSH• Incomplete pubertal development
• Low LH, low FSH• Absent pubertal development• No response to GnRH
(deRoux et al. N Engl J Med 1997;337:1597-1602.)
(Layman e al. Nat Genet 1998;18:14-15.)
![Page 36: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/36.jpg)
GnRH ResistanceGnRH Resistance
• 22 yr. old male with delayed puberty at 18,decreased libido, small (8 cc) testes, small penis
• Proposed partial loss of function mutationsin GnRHR
Labs
de Roux et al. N Engl J Med 1997;337:1597.
Testosterone = 80 ng/dL (260-690)Low FSH, LH LH pulses: Nl frequency, amplitudeSemen analysis: 39 million/mL; 5% motile
![Page 37: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/37.jpg)
GnRH
IP3 Production
GnRHR
GnRH
Membrane
Receptor binding
2nd messenger
![Page 38: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/38.jpg)
de Roux et al. N Engl J Med 1997;337:1597.
GNRHR MutationsCompound heterozygotes
Gln106Arg Arg262Gln
Gln(CAA) (CGA)
Arg Gln(CAG)(CGG)
Arg
Reduced binding Reduced IP3Reduced IP3
![Page 39: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/39.jpg)
Layman LC, Cohen DP et al. Nat Genet 1998;18:14.
GNRHR Gene Mutations in IHHGNRHR Gene Mutations in IHH
• Variable response of FSH&LH to GnRHsuggested GNRHR mutations possible
• Screened 46 IHH (32 males; 14 females)for mutations using DGGE
• 1 of 46 with GNRHR mutations (compoundheterozygote)
![Page 40: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/40.jpg)
Layman LC, Cohen DP et al. Nat Genet 1998;18:14.
GNRHR Gene Mutations
Total IP3
EC50
Tyr284Cys
Cys(TGT)(TAT)
Tyr
20% WT
75%
20X
Arg262Gln
Gln(CAG)(CGG)
Arg
75% WT
40%
10X
receptorexpression
![Page 41: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/41.jpg)
I
II1 2 3 4 5 6 7 8
7 81 2 6543 9 10 11
Age
Breasts
Testosterone
Basal LH
Stimulated LH
Basal FSH
6.0
17
No
--
< 2.0
12.3
3.3
Stimulated FSH
30
No
--
< 2.0
6.8
1.6
5.0
29
--
75
2.6
7.5
< 2.0
< 2.0
21
No
--
3.3
12.2
2.3
4.7
Layman LC, Cohen DP et al. Nat Genet 1998;18:14.
![Page 42: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/42.jpg)
Layman LC, Cohen DP et al. Nat Genet 1998;18:14.
GNRHR Gene Mutations in IHHGNRHR Gene Mutations in IHH
• Variable response of FSH&LH to GnRHsuggested GNRHR mutations possible
• Screened 46 IHH (32 males; 14 females)for mutations using DGGE
• 1 of 46 with GNRHR mutations (compoundheterozygote)
![Page 43: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/43.jpg)
Prevalence of GNRHR Mutations
Layman LC, Cohen DP et al. Nat Genet 1998;18:14.
Normosmic IHH: 1/46 (2.2%)Normosmic IHH with female: 1/14 (7%)Anosmic IHH males: 0/50*
*not included in final paper
![Page 44: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/44.jpg)
Prevalence of GNRHR Mutations
Beranova et al. JCEM 2001;86:1580-8.
Normosmic IHH: 5/48 (10%)a) Sporadic: 3/18 (16.7%)b) Autosomal recessive: 2/5 (40%)
Anosmic/hyposmic IHH: 0/60
![Page 45: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/45.jpg)
Prevalence of GNRHR Mutations
Bhagavath et al. Endocr Soc 2003
• 3/165 (1.8%) IHH patients• 1/15 (6.7%) if >2 affecteds/family• 2/38 (5.3%) if only female probands
165 IHH unrelated probands screened bydenaturing gradient gel electrophoresiswith GC-clamps (>95% mutations)
![Page 46: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/46.jpg)
GNRHR Mutations
1) ~ 15 different mutations identified2) Most compound HTZ3) May affect binding and/or signal transduction4) Phenotype varies from complete IHH to
partial IHH5) Patients do not have anosmia6) Gonadotropin response to GnRH is
variable (at least 1 pregnancy to GnRH)7) Prevalence is ~3-10% of normosmic IHH
![Page 47: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/47.jpg)
Park JL et al. Clin Endocrinol (In press).
PROP1 Gene
• Autosomal recessive form of combinedpituitary deficiency (short stature &delayed puberty)
• Deficiencies of GH, PRL, TSH, FSH, LH, & ACTH
Wu et al. Nat Genet 1998;18:147-9.
• 164 males & 20 females with IHH• No mutations identified
![Page 48: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/48.jpg)
Septo-optic Dysplasia
• Agenesis of corpus callosum, panhypopit,optic nerve hypoplasia, absent septumpellucidum
• One form due to HESX1 gene mutations• HESX1 is homeobox gene expressed in Rathke’s Pouch, pituitary primordium • Autosomal recessive, dominant
Dattani et al. Nat Genet 1998;19:125-133.
![Page 49: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/49.jpg)
Furui et al. JCEM 1994;78:107.Haavisto et al. JCEM 1995;80:1257.Suganuma et al. Fertil Steril 1995;63:989.
• Two LHB missense mutations same allele(Trp8Arg & Ile15Thr)
• In infertility and control patients• Does interfere with LH assay
LHB Polymorphisms
1. Unmeasurable: IRMA (SPAC-S kit)monoclonal Ab to whole molecule
2. Measurable: IMFMA (DELFIA):twoAbs against LH
![Page 50: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/50.jpg)
Male: delayed puberty at 17 yr.GynecomastiaInfantile penisSmall descended testesFemale distribution pubic hair
Immuno- active, Bio- inactive LH Immuno- active, Bio- inactive LH
Axelrod et al. JCEM 1979;48:279.
Labs: T= 30-80 ng/dLLH = 30 mIU/mLFSH = 26 mIU/mL
![Page 51: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/51.jpg)
Immuno- active, Bio- inactive LHImmuno- active, Bio- inactive LH
Axelrod et al. JCEM 1979;48:279.
• Exogenous T induced secondary sexcharacteristics; then d/c
• hCG restored adult phenotype &sperm (1 million/cc after 2 mo. &11 million/cc, 50% motility, 50% nl)
• T also increased to exogenous LH• Testicular Bx: maturation arrest, no Leydig
![Page 52: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/52.jpg)
Weiss et al. N Engl J Med 1992;326:179.
LHB Gene Mutation• Homozygous LHB gene missense mutation
in exon 3 (Gln54Arg)
1. Detected by dimer-specific IRMA2. Undetectable by RRA
• Mutant LH not capable of receptor binding• Autosomal recessive• Heterozygotes probably normal
![Page 53: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/53.jpg)
Human FSHB Mutations: Females
• No breast development or menses (1,2)• Partial breast development (3)• Low FSH, High LH• Low estradiol• Immature ovarian follicles (antral)• Infertility
1) Matthews et al. Nat Genet 1993;5:83-86.2) Layman et al. N Engl J Med 1997;337:607-11.3) Layman et al. JCEM 2002;87:3702-7.
![Page 54: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/54.jpg)
• Low testosterone • No clinical effects (no hirsutism)• Clinical studies
Human FSHB Mutations: Female
Barnes et al. N Engl J Med 2000;343:1197-98.
FSH Testosterone
Layman et al. N Engl J Med 1997;337:607-11.
Barnes et al. Hum Reprod 2002;17:88-91.
+LH
![Page 55: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/55.jpg)
Human FSH Mutations: Males• Normal puberty or absent puberty• Low FSH, High LH• Low or normal testosterone • Small testes• Azoospermia• Infertility
Lindstedt et al. Clin Chem Lab Med 1998;36:663-65.Phillip et al. N Engl J Med 1998;338:1729-32.Layman et al. JCEM 2002;87:3702-7.
![Page 56: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/56.jpg)
• Low testosterone • Azoospermia
Human FSH Mutations: Male
FSH TestosteroneSperm
Phillip et al. N Engl J Med 1998;338:1729-32.
+LH
![Page 57: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/57.jpg)
Immuno- ; Bio- Untrnsf = Untransfected cells.
Val61X Tyr76X MediaUntrnsf.Cys51Gly
50
100
FSHmIU/mL
WT
Layman et al. JCEM 2002;87:3702-7.
FSH Levels in vitro Cell Lines
![Page 58: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/58.jpg)
Hypogonadotropic HypogonadismHypogonadotropic Hypogonadism
1. No GNRH1 gene mutations, so rare2. KAL1: 10-15% male IHH patients3. KAL1 gene expression explains associated
anomalies4. FGFR1 mutations in 10% male KS? 5. NROB1 affect hypothalamic, pituitary,
adrenal function; M + F6. GNRHR: variable phenotype:M + F 7. LEP & LEPR: obesity & HH8. Most causes of inherited IHH unknown
![Page 59: Genetics of Hypogonadotropic Hypogonadism Lawrence C. Layman, M.D. Professor Chief, Section of Reproductive Endocrinology, Infertility, & Genetics Department](https://reader034.vdocuments.us/reader034/viewer/2022051415/56649d295503460f949fe036/html5/thumbnails/59.jpg)
GNRHR
NROB1LEP/LEPR
LHFSH
HYPOTHALAMUS
PITUITARY
GONAD
SteroidsGametes
GnRH
LHBFSHB
PROP1
HESX1
FGFR1
KAL1