Genetics: Inheritance of Human Disease Flashcards
what forms on non-mendelian inheritance are there
- mitochondrial
- mosaicism
- methylation/imprinting
how is an autosomal dominant disease seen in families
- seen in all generations
- 50% of affecting child if parent affected
- M and F equally likely to be affected
how is an autosomal recessive disease seen in families
- may not be seen in all generations
- 25% of affecting child if parent is a carrier
- more likely to affect child if parents are related
how is an X-linked disease seen in families
- females are carriers, expressed in males
- 50% females pass onto males and 50% females as carriers
- no male-to-male transmission
- females will express some features of disease
how is X-inactivation important in X-linked diseases
females will likely only show mild features of the disease half their cells will express working copies of the gene
how can SNPs affects genes
- most have no effect
- some can destroy a gene, but not cause disease
what is a copy number variant
during replication the genome may have extra or missing copies of genes compared to another individual
what is the environmental contribution to mendelian disorders
small
describe multifactorial disease
genetic changes are treated as another risk factor, penetrance for 1 mutation is low, need multiple to build up
how can precision medicine be used in
- mendelian disorders
- multifactorial disease
- precision medicine can be effective as there will be one gene to target
- precision medicine difficult as many genes lead to the disease
