Week 9: Calculation and risk assessment Flashcards
What is the coefficient of inbreeding?
The probability that an individual will inherit two identical alleles for a given gene
What is inbreeding?
Process of mating genetically similar organisms
In animals leads to:
-new breeds
-Preservation of traits
-Risk for undesired AR traits
Differentiate consanguinity from incest
Consanguinity: being descended from the same ancestor
Incest: sexual intercourse between closely related persons that are forbidden by law or the crime of sexual intercourse with parent, child, sibling, grandchild
What is the law in wisconsin for marriage between closely related people?
Minimum distance of kin allowed is second cousins
How does the prevalence of consanguinity differ between middle east/africa and north america/west europe/oceania?
Middle east/north africa: 20-50% of marriages consanguineous
Western europe/north america/oceania: <1%
List 4 prenatal risks to consanguineous couples
- Congenial abnormalities
- Intrauterine fetal demise
- Neonatal death
- DD/ASD
What is the coefficient of relationship (COR)?
Related to the consanguineous couple and indicates the proportion of genes on average they would be expected to share by descent from common ancestors
MEASURES THE DEGREE OF CONSANGUINITY
What is the coefficient of inbreeding (COI)?
Relates to the child of a consanguineous relationship and indicates the probability the child will be homozygous for a specific allele from common ancestor
What is the equation for COI?
F=∑(1/2)^n
Identical by descent (IBD)= inherited allele(s) from common ancestor
What are some psychosocial considerations for consanguineous relationships?
-“criminal” component to incestual relationships in US
-Considered stigma whereas a cultural norm in other regions
-Parental guilt with understanding degree of relatedness likely cause of fetal anomalies
-Challenges associated with reproductive risks- AR conditions
Risk assessment for a consanguineous couple experiencing loss could include what?
-What is the risk to future pregnancies?
-Does this fully explain all their pregnancy losses?
-Reproductive options?
