What are polygenic traits
Traits that are affected by more than 1 gene
What are quantitative MFIs
Ones that can be measured on a scale
What are threshold MFIs
Ones that are (threshold passed) all or nothing
How can you determine the recurrence risk of MFI traits
square rot of the incidence of the trait
What is the overall recurrence risk of any given trait
4%
What family hx suggests gonadal mosaicism
Negative family hx for disease but 2+ offspring with it
How do gonadal mosaicisms come about
de novo mutations
What is genomic imprinting and give example(s) of diseases in this category
Epigenetic modifications of the zygote. Some traits/genes are more likely to be passed on by one parent. Prader-Willi and Angelman syndromes
Prader-Willi syndrome characteristics and causes
lack of expression in paternal allele. Can be the result of maternal UPD or paternal deletion
Angelman syndrome characteristics and causes of Angelman’s syndrome
Lack of expression of maternal allele. Can be result of paternal UPD or maternal deletion
What is anticipation
The increase in severity of a disorder in proceeding generations
what is a premutation
just like it sounds–last stage in anticipation before mutation or trait becomes expressed
