Single-Gene Disorders Flashcards
AD disease inheritance chx
Observed in multiple generations of a pedigree
Males and females affected equally
AD diseases
- Familial hypercholesterolemia
- Huntington
- NF type 1
- Marfan
- Acute intermittent porphyria
AR disease inheritance chx
Offspring must inherit 1 copy of gene from both parents
Typically seen in one 1 generation of a pedigree
AR diseases
- Sickle cell anemia
- CF
- PKU
- Tay-Sachs
X-linked recessive inheritance chx
Seen much more in males
Skipped generations on Pedigree
X-linked recessive senario
Affected male + homozygous normal female
All of daughters will be heterozygous carriers
All sons will be homozygous normal
X-linked recessive senario
Normal male + Carrier female
Half of sons affected
Half of daughters will be carriers
X-linked recessive diseases
- Duchenne
- Lesch-Nyhan
- G6PD
- Hemophilia A and B
- Red-green color blindness
- Menke’s
- OTC deficiency
- SCID
X-linked dominant inheritance chx
100% penetrance in males
Seen twice as much in males
Seen in multiple generations on pedigree with no skipping
Fragile X syndrome genetics
X-linked dominant
Fragile X syndrome symptoms in males
- Mental retardation
- Large ears
- Prominent jaw
- Macro-orchidism
Pleiotropy is
Single dease-causing mutation affects multiple organs
Locus Heterogeneity is
when the same disease phenotype can be caused by mutation in different loci
Diseases showing delayed age of onset
- Acute intermittent porphyria
- Huntington
- Hemochromatosis
- Famililal Breast cancer
Diseases showing anticipation
- Huntington
- Fragile X
- Myotonic dystrophy
- Freidreich ataxia