Lecture 7 Flashcards
What is a locus?
The location of a gene on a chromosome.
What is an allele?
The particular form of the gene inherited from your mother or father
What does dominant mean?
One copy of the gene causes the disease
What are the genotype and Phenotype?
Genotype - The genetic makeup of the individual
Phenotype - The physical expression of the genotype
What is autosomal dominant?
The gene at one allot determines the phenotype
What are some characteristics of autosomal dominant?
50% of offspring affected, male = female, does not skip generations, penetrance cane be <100%
What is autosomal recessive?
The genes at both alleles determine the phenotype
What are some characteristics of autosomal recessive?
25% of offspring affected, male = female, 50% of offspring carriers, tends to skip generations
What are types of autosomal recessive?
Sickle cell anaemia, cystic fibrosis, albinism
What is X-linked recessive? when the mother is affected
50% male affected, 50% female carriers and mother–> transmission
What is X-linked recessive? when the father is affected
No male - male transmission, 100% of daughters carriers, 100% of sons normal
Give examples of X-linked recessive
Haemophilia, muscular dystrophy
Where is mitochondrial DNA found?
The ova, maternal inheritance
What are some features of mitochondria DNA?
Much shorter, no introns, different genetic code and mutations are 5-10x more common
What do mitochondrial diseases tend to affect?
Brain, eye and skeletal and cardiac muscle
