applications A & B Flashcards
(59 cards)
medical genetics
focuses on diagnosis and management of medical, psychological, and social aspects of diseases involving the mutation or influence of genes
family focus of medical genetics
related to both medical care/management of patient and forward-looking consideration of future offspring
3 types of hereditary disease
- mendelian conditions
- chromosomal conditions
- multifactorial conditions
mendelian conditions
- caused by mutation of single gene
- autosomal dominant/recessive, X-linked dominant/recessive, Y-linked, mitochondrial
- inherited from one or both parents, or new mutation
chromosomal conditions
- extra chromosome, missing chromosome, duplication/deletion of segment, structural rearrangements
- developmental/physical abnormalities can result due to human sensitivity Gene Dosage
- autosomes or sex chromosomes
multifactorial conditions
- multiple genes and environmental factors
- increased likelihood = inherited susceptibility
- differing mutant allele frequencies
ex. of chromosomal condition
trisomy 21
ex. of multifactorial condition
diabetes
different types of testing for genetic conditions
- molecular analysis of DNA/RNA
- biochemical analysis
- chromosome analysis
molecular analysis tests
useful when suspicion of specific Mendelian condition
biochemical analysis
tests blood or tissues for absence or presence of certain proteins as well as levels
chromosome analysis
chromosomal causes of:
- fetal or infant malformations
- mental impairment/physical abnormalities
- long-term infertility in adults
carrier testing
identifies individuals who are heterozygous for recessive conditions or have chromosomal abnormality that could produce condition in future child
do carrier individuals who undergo carrier testing have the genetic condition?
no
ex. of carrier frequency being so high that carrier testing is a public health effort
Tay-Sachs disease in Ashkenazi Jewish populations
pre-symptomatic testing
used for genetic conditions with l ate age of onset
ex. of disease tested with pre-symptomatic testing
autosomal dominant Huntington disease
- by age 40, only about 50% of people show condition
newborn testing
consists of set of mandated genetic tests that together require only a few drops of blood from a “heel stick”
in 2003, the advisory committee established the ______________ ________________ ____________ that contained list of genetic disease recommended for testing
Recommended Uniform Screen Panel (RUSP)
what do nearly all states test for
34 “core” hereditary conditions
additional conditions that states might include testing for
25 “secondary” conditions
what is newborn genetic screening considered?
public policy intended to save lives, reduce medical costs, and support well-being of families
what do positive test results of genetic screening allow
immediate start of treatment
prenatal testing
performed during pregnancy to detect a condition in a fetus including chromosomal abnormalities and developmental defects
