phenotypic variability Flashcards
how does environment affect phenotypic variability
expression of gene is modified by environmental factors
eg haematochromatosis - low iron intake improves outcomes
wide range of variability implies environmental
how does sex cause phenotypic variability
where someone’s sex affects gene expression
eg in haemochromatosis, women lose iron through menstruation so less build up
how do modifiers affect phenotypic variability
when the expression of one gene is directly impacted by the expression of another
eg in cystic fibrosis
what does it mean by mutation phenotypic variability
where different mutated subtypes of same gene have different presentations
eg duchenne and becker muscular dystrophy
what does unstable phenotypic variability mean
trinucleotide repeat disorders
where an increased number of nucleotide repeats ( >27) cause more severe phenotypes throughout generations
eg huntingtons
