Genetic disordersGenetic disordersCaused by:Caused by:

~ _________________________ ~ _________________________ ________________________________________________

OrOr~ _________________________ ~ _________________________

__________________________________________________

Altered ChromosomesAltered Chromosomes ## can change due to _________________ can change due to _________________

____________________________________________________________________

structurestructure can change _______________ can change _______________ __________________________________ __________________________________ ____________________________________________________________________

( Remember: chromosomes are DNA ( Remember: chromosomes are DNA wrapped around histones. When the wrapped around histones. When the DNA is altered the structure changes)DNA is altered the structure changes)

________________ && __________________

- Substance that can Substance that can cause a mutationcause a mutation- ExEx--

- UV LightUV Light- X-RaysX-Rays- RadiationRadiation- VirusesViruses- TobaccoTobacco

1-1- _______________ _______________ Mutation-Mutation- reproductive cells reproductive cells (sperm & egg)(sperm & egg)

2-2- __________ __________ Mutation-Mutation- body cells body cells (types of Cancer)(types of Cancer)

Types of Types of structural structural MutationsMutations1- 1- ________________-________________-

piece of chromosome piece of chromosome is lostis lost(Cri-du-Chat or Prader-(Cri-du-Chat or Prader-Willi Syndrome)Willi Syndrome)

2- 2- ____________________________________- - piece breaks off & piece breaks off & reattaches upside reattaches upside downdown

3- 3- ___________________-___________________- piece breaks off and piece breaks off and attaches to a different attaches to a different chromosomechromosome

4- 4- ____________________-____________________- removal of a single removal of a single DNA DNA nucleotidenucleotide(one nitrogen base is substituted with (one nitrogen base is substituted with another)another)Example-Example-** ** OriginalOriginal - The fat - The fat ccat ate the wee rat.at ate the wee rat.** ** Point MutationPoint Mutation - The fat - The fat hhat ate the wee at ate the wee

rat.rat.

Carcinogen-Carcinogen- mutation that may cause cancer mutation that may cause cancer

Cri du Chat Syndrome: Cri du Chat Syndrome: ______________________

CharacteristicsCharacteristics- High pitched - High pitched mewing cry as an mewing cry as an infantinfant- Slant of the eyes- Slant of the eyes- Mental - Mental retardationretardation- _________________ - _________________ __________________ __________________ ____________________________________

Prader –Willi Syndrome: Prader –Willi Syndrome: __________________________CharacteristicsCharacteristics

- Infants are weak- - Infants are weak- sucking reflex is poor & sucking reflex is poor & feeding is difficultfeeding is difficult

- _______________________ - _______________________ ____________________________________________

- Children become - Children become extremely obeseextremely obese

- ____________________________________________- Short statureShort stature- Poor sexual - Poor sexual

developmentdevelopment- Behavioral issues- Behavioral issues

Changes in the Changes in the Chromosome NumberChromosome Number

______________________________________________-- chromosomes chromosomes fail to separate fail to separate during Meiosis; will cause during Meiosis; will cause a lack of a chromosomes or will give you an a lack of a chromosomes or will give you an extra chromosomeextra chromosome

2 Types2 Types1- 1- ______________________________-- lack a lack a

chromosomechromosome__________________________________________________________________

- _______ chromosomes = - _______ chromosomes = XOXO-________________________-________________________- webbed neck- webbed neck - short- short- swelling at wrists & ankles- swelling at wrists & ankles- ______________________________- ______________________________

-- 2. 2. TrisomyTrisomy-- ___________________________ ___________________________- ex: - ex: ____________________________________(Trisomy 21)-(Trisomy 21)- males males

& females, decreased muscle tone, slanting & females, decreased muscle tone, slanting eyes, small mouth with protruding tongue, eyes, small mouth with protruding tongue, mental retardationmental retardation

Types of NondisjunctionTypes of NondisjunctionKlinefelter’s SyndromeKlinefelter’s Syndrome

((____________________________________________)- _____________________, tall )- _____________________, tall (long legs with short trunk), infertile, low IQ, (long legs with short trunk), infertile, low IQ, enlarged breast tissue (a type of Trisomy)enlarged breast tissue (a type of Trisomy)

Detecting Human Genetic Detecting Human Genetic DisordersDisorders

Genetic screening-Genetic screening- examine a person’s examine a person’s genetic make-upgenetic make-up(Karyotype, Blood tests)(Karyotype, Blood tests)

2 methods:2 methods:1- 1- ____________________- ____________________-

amniotic fluid withdrawalamniotic fluid withdrawal2- 2- ____________________ ____________________

(CVS)-(CVS)- take a sample of take a sample of villi (_____________________ villi (_____________________ _____________________)_____________________)

**Both produce **Both produce Karyotype**Karyotype**

Detecting Human Genetic Detecting Human Genetic DisordersDisorders

Advantage of bothAdvantage of both: - Physicians can : - Physicians can detect more than detect more than __________________________________________________________________

Disadvantage of AmniocentesisDisadvantage of Amniocentesis: most : most conditions are incurable and the results conditions are incurable and the results ____________________________________ ____________________________________ (abortion at this time is very difficult)(abortion at this time is very difficult)

Disadvantage of CVS:Disadvantage of CVS: __________________ __________________ ________________________or miscarriage but ________________________or miscarriage but it comes back b/4 1it comes back b/4 1stst trimester is over trimester is over

Genetic Traits & Genetic Traits & DisordersDisordersGenetic Disorder-Genetic Disorder- disease disease

or set of conditions that or set of conditions that have a genetic basis.have a genetic basis.

1- 1- Single Allele Trait-Single Allele Trait- 1 1 allele controls the traitallele controls the trait

A) A) ____________________: ____________________: Ex: Huntington’s disease, Ex: Huntington’s disease,

Achondroplasia Achondroplasia (dwarfism), Cataracts, (dwarfism), Cataracts, Polydactyl)Polydactyl)

B) B) __________________________________________: : Ex: albinism, cystic fibrosis, Ex: albinism, cystic fibrosis,

sickle cell anemia, PKU, sickle cell anemia, PKU, MarfanMarfan

Genetic Traits & Genetic Traits & DisordersDisorders2.- 2.- ______________________ ______________________ 3 3 or more alleles of the same or more alleles of the same gene code for a single traitgene code for a single traitEx- Blood Groups (A, B, O)Ex- Blood Groups (A, B, O)

3- 3- ______________________-______________________- traits that are controlled by traits that are controlled by many genes (Skin, Hair & many genes (Skin, Hair & Eye color, Height, Foot Eye color, Height, Foot size)size)

4- 4- ______________________-______________________- phenotype depends on phenotype depends on gender and hormones gender and hormones (Baldness)(Baldness)

Genetic Traits & Genetic Traits & DisordersDisorders

5- 5- ____________________________________-- found only one the found only one the X Chromosome X Chromosome

Examples-Examples-Colorblindness, Colorblindness, Fragile- X, Fragile- X, Hemophilia, Hemophilia, Muscular Muscular Dystrophy, Dystrophy, Ichthyosis simplex Ichthyosis simplex (Scaly skin)(Scaly skin)

Heterozygous advantageHeterozygous advantageMalaria and sickle Malaria and sickle

cell anemiacell anemia ______________________________ ______________________________ ______________________________ ______________________________ ______________________________