L15: Patterns of Inheritance Flashcards
What two components contribute to human disease?
Environmental and genetic factors
Name some diseases caused by genetic factors
- Duchenne muscular dystrophy
- Haemophilia
Name some diseases caused by environmental factors
- Tuberculosis
- scurvy
Name some human diseases caused by both environmental and genetic factors
- Spina bifida
-diabetes
-ischaemic heart disease
What characterises genetic factors in causing human disease?
- Rare
- genetics simple
- unifactorial
- high recurrence rate
What characterises environmental factors causing human disease?
- Common
- Genetics complex
- Multifactorial
- Low recurrence rate
What can mutations in genes cause?
Loss or gain of gene function
What ways can mutations affect genes?
- Involve a single gene (Mendelian inheritance)
- Involve a chromosomal segment (or whole chromosome) which affects thousands of genes
- Involve several genes acting with environmental influences (multifactorial inheritance)
What are multifactorial diseases?
Variants in genes casuing alteration in function
What are mitochondrial disorders?
Generally affect organ systems with high energy requiments
What are chromosomal disorders?
Chromosomal imbalance causes alternation in gene dosage
What are somatic disorders?
Cause cancer,inactivation of both alleles (two’hits’ ) of a gene involved in growth
Where are genes controlling structure and function of mitochondria found?
Both mitochondrial and nuclear DNA
What are the 3 types of single gene disorders?
- Autosomal dominant
- Autosomal recessive
- x-linked
What is a genotype?
A pair of alleles at a locus
