Human Traits and Diseases Flashcards
1
Q
Autosomal Recessive Diseases
A
- Tay Sachs
- Albinism
- Cystic Fibrosis
- Sickle Cell
- PKU
2
Q
Autosomal Dominant Diseases
A
- Breast Cancer
- Huntington’s
- Achondroplastic Dwarfism
3
Q
X-linked recessive disease
A
-hemophilia
4
Q
Cystic Fibrosis
A
- encodes a transmembrane protein (CFTR)
- regulates ion transport across cell membrane
- mutant allele mutates the CFTR protein causing ion imbalance
- excessive loss of NaCl
5
Q
Sickle Cell Anemia
A
- Abnormal form of hemoglobin
- glutamic acid replaced with baline
- heterozygous are malaria resistant
6
Q
PKU
A
- deficiency in enzyme phenylalanine hydroxylase
- increased phenylalanine levels in ppl with PKU
- high levels trigger the reaction that converts phenylalanine to phenylpyruvic acid –> very neurotoxic to babies brain
- deficient tyrosine
7
Q
PKU and pregnancy
A
- during pregnancy women have increased levels of phenylalanine and pyruvic acid
- fetus will suffer from maternal PKU
- mother must go back on restricted diet
8
Q
Tay Sachs Disease
A
- deficiency of hexA
- GM3 gangliosides accumulate in the brain
- cerebral motor function, early childhood death
9
Q
why is tay sachs not treatable
A
blood brain barrier
10
Q
preimplantation: genetic diagnosis
A
one cell removed for analysis
-if genetically healthy it is implanted back into mother
11
Q
Huntington’s
A
- dominant mutation
- (CAG nucleotide repeat)
- need more than 35 repeats
- offspring have a 50% chance of inheriting
- CAG encodes a flutamic acid
- polyglutamate tract is cleaved by caspase (makes them neurotoxic)
- by blocking caspase huntington’s can be solved
12
Q
Achondroplastic Dwarfism
A
- Dominant
- Risk increases with paternal age
