Fitness

b) what effect on fitness do we expect to see w/ dom disease?

c) what do we actually see?

average number that reach reproductive age divided by avaerage of population

b) reduced fitness ie lower incidence in next generation

c)constant incidence meaning new mutation make up deficit

parents: usually not affected

1/4 of children from two heteros will be affected

parents are often distantly related

male=femal affected

must have come from affected parent except in reduced penetrance and new mutations

50% affected in sibship

autosomal dominant disorder which shows reduced penetrance

affected present with rickets

2x more females than males

never father to son

males have 50% of getting from mother if she is heterozygote. male is hemizygote, will def pass gene on to daughter

phenotype appears if no other allele is present ie hemizygotes(males) and homo females

Usually more males than females

father to daughter transmission

Ex. Hemophilia A

AUTOSOMAL DISEASE

influeces traits in one sex and not the other. ie male pattern baldness and breast cancer

person w/ genotype that does not express phenotype

typically seen in dominant disease

diffs in severity of phenotype and age of onset

mostly in dom disease

a) Locus Heterogeneity

b) allelic heterogeneity

a) involvement of genes on diff loci, genes are placed differntly in genome.

b) same gene, diff allelic mutation

ie B thalesemia has 2 forms.

looks like a genetic disorder but caused by enviornment

deletion or duplication of large part of chrom.

ie diGeorge/catch 22