following patterns of inheritance. humans cannot undergo breeding experiments for use in genetic...
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FOLLOWING PATTERNS OF INHERITANCE
FOLLOWING PATTERNS OF INHERITANCE
Humans cannot undergo breeding experiments for use in genetic studies – ethical implications
FOLLOWING PATTERNS OF INHERITANCE
PEDIGREE – a type of flowchart that uses symbols to show the inheritance patterns of traits in a family over many generations
- a way to analyze how traits run in a family
- a way to visualize patterns of inheritance
- can uncover genotypes of particular family members
PEDIGREE
PEDIGREE
AUTOSOMAL INHERITANCE
AUTOSOMAL INHERITANCE: inheritance of traits whose genes are found on autosomes in humans(chromosomes 1-22)
a) AUTOSOMAL DOMINANT: the disease causing allele is dominant and is present in an individual with one or both copies of the allele
b) AUTOSOMAL RECESSIVE: the disease causing allele is recessive and both copies of the allele is required
AUTOSOMAL INHERITANCE
AUTOSOMAL INHERITANCE PATTERNS (Page 220)
CHROMOSOME NUMBER
CONDITION INHERITANCE PATTERN
DESCRIPTION
4 Huntington disease
Autosomal dominant
Loss of muscle control and decline in mental ability
7 Cystic fibrosis
Autosomal recessive
Thick mucus build up in lungs making breathing difficult
11 Sickle cell anemia
Autosomal recessive
Red blood cells irregularly shaped
AUTOSOMAL INHERITANCE
AUTOSOMAL INHERITANCE PATTERNS (Page 220)
CHROMOSOME NUMBER
CONDITION INHERITANCE PATTERN
DESCRIPTION
12 Phenylketonuria Autosomal recessive
Prevents breakdown of phenylalanine, delays in cognitive function
13 retinoblastoma Autosomal dominant
Tumors in retinal of young children
15 Marfan syndrome
Autosomal dominant
Affects connective tissue leading to weakness of heart, blood vessels and skeleton
AUTOSOMAL INHERITANCE
AUTOSOMAL INHERITANCE PATTERNS (Page 220)
CHROMOSOME NUMBER
CONDITION INHERITANCE PATTERN
DESCRIPTION
15 Tay-sachs disease
Autosomal recessive
Progressive destruction of nervous system, accumulation of lipids
18 Niemann-Pick disease
Autosomal recessive
Brain and nervous system impairment due to accumulation of lipids
19 Maply syrup urine disease
Autosomal recessive
Inability to break down three amino acids, leading to nerve degeneration
AUTOSOMAL INHERITANCE
AUTOSOMAL INHERITANCE PATTERNS (Page 220)
CHROMOSOME NUMBER
CONDITION INHERITANCE PATTERN
DESCRIPTION
20 Adenosine deaminase deficiency causing severe combined immunodeficiency disease
Autosomal recessive
Deficiency in enzyme adenosine deaminase resulting in minimal immune response and susceptibility to disease
AUTOSOMAL DOMINANCE INHERITANCE
Autosomal dominant pedigrees are common when the child is not affected and both parents are
- Parents are hetoerzygous
AUTOSOMAL DOMINANCE INHERITANCE
HUNTINGTON DISEASE (autosomal dominance)
- Affected: AA or Aa; Unaffected aa
- Brain deteriorates over a period of 15 years
- Symptoms: decreased muscle co-ordination, erratic body movements, personality changes, decline in mental abilities
- Lethal, no cure
AUTOSOMAL DOMINANCE INHERITANCE
HUNTINGTON DISEASE (autosomal dominance)
AUTOSOMAL DOMINANCE INHERITANCE
HUNTINGTON DISEASE (autosomal dominance)
Find the genotypes of each person
AUTOSOMAL DOMINANCE INHERITANCE
HUNTINGTON DISEASE (autosomal dominance)
Find the genotypes of each person
AUTOSOMAL RECESSIVE INHERITANCE
Autosomal recessive inheritance is common when two unaffected parents can have an affected child
- Parents are carriers
AUTOSOMAL RECESSIVE INHERITANCE
CYSTIC FIBROSIS (autosomal recessive disorder)
- Unaffected: Aa or A; Affected aa
- Most common fatal genetic disorder affecting young Canadians
- Defective protein disrupting movement of Cl- across cell membranes which disrupts movement of water across cell membranes- Results in thickened mucus that builds up in the organs of the
body- Breathing and digestive problems
- No cure
AUTOSOMAL RECESSIVE INHERITANCE
CYSTIC FIBROSIS (autosomal recessive disorder)