Lecture 8- Advanced Mendelian Genetics Flashcards
An allele that codes for the normal working copy of the …… is usually …….
Enzyme
Dominant
Mutant alleles that encode non functional ….. are usually …….
Enzymes
Recessive
Haploinsufficiency
Two wild type alleles:
Effect on enzyme level
Phenotype
Normal enzyme level
Normal phenotype
Haploinsufficiency
One wild type allele
One mutant allele:
-effect on enzyme level
-phenotype
Half normal amount of enzyme
Normal phenotype
Haploinsufficiency
two mutant alleles:
-effect on enzyme level
-phenotype
No enzyme
Mutant phenotype
Haploinsufficiency
Presence of half the normal amount of a protein
Not enough for normal phenotype
eg. Rubinstein-Taybi Syndrome
Rubinste-Taybi syndrome
Autosomal dominant syndrome
Arrises as a new mutation in gene encoding CBP
Malformation of heart, broad thumbs and big toes, beaked nose
Haplosufficient
One good/normal allele is enough to result in a normal phenotype in heterozygous individuals
Dominant negative allele
Mutations that prevent the action of a protein
Mutant protein inhibits action of non-mutant molecules
Protein product doesn’t work
Dominant negative allele
Two wild type alleles:
Protein level
Phenotype
Normal protein level
Normal phenotype
Dominant negative allele
One wild type, one mutant allele:
Protein level
Phenotype
Half amount of normal protein- effect is inhibited
Mutant phenotype
Dominant negative allele
Two mutant alleles:
Protein level
Phenotype
No protein
Mutant phenotype
Osteogenesis imperfecta
Affects type 1 collagen
Caused by mutations affecting amount of collagen or quality of collagen
Fruit colours in pepper
Determined by red/ yellow pigment and build up of chlorophyll
Red: R- C-
Brown: R- cc
Yellow: rr C-
Green: rrcc
