Epidemiology, signs and symptoms of Inherited Retinal Dystrophies Flashcards
What are the different main retinal dystrophies?
~ Retinitis pigmentosa
~ Cone/Rod dystrophy
~ Congenital stationary night blindness
~ Stargardt’s disease
~ Best’s vitelliform dystrophy
What is a genotype?
~ Your genetic classification
~ e.g. you have a mutated gene that codes for a protein that leads to a disease
What is a phenotype?
~ Physical appearance
~ e.g. you actually show the disease
* Whether this happens or not depends upon the mode of inheritance (dominant or recessive) and the penetrance
What is X-linked?
~ The gene is coded on the X chromosome
~ Females have 2, males have 1
What is autosomal?
~ The gene is coded on one of the 22 non-sex chromosomes
~ You get one of these from your mother and one of these from your father
What is dominant?
~ In order to show the phenotype you only require 1 mutated gene
What is recessive?
~ In order to show the phenotype you require 2 copies of the mutated gene
What is penetrance?
~ Even if you have the genotype you may not get a severe form of the disease