Genetic Inheritance - Week 1 PBL Flashcards
What is haploinsuffiency?
Where only half of the required protein is produced so not enough for function
What is genetic anticipation?
The disease is more severe after each generation as more of the mutated gene repeats = greater effects
What is a consanguineous relation and its relevance to genetics?
Parents who are within the same genetic family, increase risk of recessive disorders in children
What is the coefficient of relationship?
Probability of related individuals sharing a specific gene
An example of an autosomal dominant disorder?
Neurofibromatosis type II - overgrowth of Schwann cells
An example of an auto recessive disorder?
Oculocutaneous albinism - lack of melanin production
What is polygenic inheritance?
Variation of traits due to the combined effects of multiple genes
What are multifactorial traits?
When environmental traits are believed to cause variation in quantitative traits
What is heritability?
The proportion of variability due to genetic factors and not environmental
How to assess heritability?
Familial risks
Twin studies - compare frequency of phenotype in monozygotic and dizygotic twins
What is the liability threshold model?
The distribution of risk factors in general population and family members of affected individuals
List 3 multifactorial diseases
CAD
Hypertension
Diabetes mellitus
How to tell autosomal dominant and recessive form a family tree?
AD: vertical pattern, affecting multiple generations
AR: horizontal pattern, affecting same generations
