Mendelian Inheritance Flashcards
Pedigree
Proband
Key Types of Mendelian Inheritence
Y-Linked Traits
Autosomal Recessive
The risk of a child being born with an autosomal dominant disorder to parents one of whom has the disorder is:
10%
25%
50%
75%
Cannot be determined
50%?
Don’t Set too much store on this you weren’t paying attention.
Autosomal Dominant
X-Linked Recessive
X-Linked Dominant
Penetrance
Genetic testing helps determine if the patient didn’t inherit that allele or if it is non-penetrant.
Expressivitiy
Expressivisity — Not black and white (Unlike Penetrance) differing severities.
Huntington’s disease
Huntington’s disease — not everyone who has a mutation for Huntington’s disease but they won’t have it. Penetrance is 90%
Retinoblastoma
Retinoblastoma — has variable penetrance.
Sleeper
Sleeper — Someone who has the mutation but doesn’t show it.
Non-Traditional Modes of Inheritence
Mitochondrial Maternal Effect
Nervous system and muscular system are the most effected with mitochondrial diseases.
When cytokinesis occurs the mitochondria randomly split and can be split into any proportion and statistically it’s 50-50 but it can be anything.
Red Mitochondria produce energy. Blue don’t produce energy.
Heteroplasmy— Heteroplasmy is the presence of more than one type of organellar genome (mitochondrial DNA or plastid DNA) within a cell or individual. It is an important factor in considering the severity of mitochondrial diseases.
Mitochondrial Diseases have a kind of moacism
Genetic Anticipation
Amniocentesis
Chorionic Villus Sampling
NIPT
Frequency of Downsyndrome and Maternal Age
Examples of Genetic Disease and Prenatal Testing
Summary of Key Points
Compare and Contrast Key Mendelian Inheritence Patterns
