Lecture 5 - Genetics in medicine Flashcards
Genetic disciplines
Medical genetics - explores the genetic contributions to the etiology, pathogenesis, and natural hx of diseases and disorders
Clinical genetics - the diagnosis, prognosis, & treatment of genetic diseases
Genetic v. Familial v. Hereditary
Genetic - pathophysiology of the disorder is based on changes in DNA
Hereditary - the DNA change is in the germ cells
Familial - runs in the family (may not always be genetic)(common environment)
Ex. Multiple sclerosis
Human Genome
- 3.2 Gb (3.2 billion base pairs)
- aprox. 20k known genes
- 3k genes associated with disease
- Coding region (exons) = 64 Mb (2%)
- 85% of disease causing mutations are in exons
Mutation v. Polymorphism
Mutation is any change/deviation from the normal DNA code
Polymorphism is a mutation (variant) that occurs in at least 1% of general population
Internet resources for human genetics
ornl.gov
OMIM (ncbi)
GeneReviews (ncbi)
Geneticalliance.org
Epidemiology of genetic conditions in clinical medicine
- 60% of pediatric hospital admissions are due to a condition with a genetic basis
- 40% of adult hospital admissions are due to a condition with a genetic basis
- Genetic background has a 30% contribution to a person’s health
- 2-3% of all newborns have recognizable anomaly and additionaln 2-3% ahve unrecognizable anomaly
- 3% of US pop. has intellectual disability
- 5% learning disability in all school age children