Genetics & Heredity Flashcards
color blindness
sex-linked or x-linked trait
recessive trait
Allele
alternative form of a gene (ie, different eye colors)
Genotype
genetic makeup
Phenotype
Physical makeup
Dominant Allele
Uppercase letter
Recessive Allele
Lowercase Letter (of the same capital letter)
Both Alleles present?
the one that is ‘seen’ is the dominant one
Mendelian Genetics
certain patterns of how traits are passed from parents to offspring
Two Dominant Genes
EE, homozygous
Two Recessive Genes
ee, Homozygous recessive
one of each gene
Heterozygous
one gene tracking
monohybrid
two gene tracking
dihybrid
P generation
grandparents/ the starters, parental generation
F1 Generation
Children
filial generation
F2 Generation
Grand-children
Filial two generation
Phenotypic ratio
numerical comparison of how many offspring will have one phenotype versus another
Autosomal Recessive Disorders
1-22 autosomes
NN = normal
Nn = carrier
nn = disorder
cystic fibrosis
autosomal recessive disorder
excess mucus in lungs + intestines
most common lethal genetic disease
highest among caucasians
sickle cell syndrome
autosomal recessive disorder
hemoglobin gets fucked in low oxygen environment
african descent
1:500 worldwide
Autosomal Dominant Disorders
1 copy of mutated gene
more easily removed from the gene pool
Huntington’s Disease
autosomal dominant disorder
neurological disorder (develops into dementia)
onset 40s
Tay Sachs Disease
autosomal recessive disorder
neurological disorder
die by age 4
ashkenazi jew
Achondroplasia
Dwarfism
autosomal dominant disorder
non-mendelian genetics
multiple alleles
co-dominance
both parents are presented (blood type)
incomplete dominance
neither parent present
pleiotropy
sinlge gene –> many phenotypes, multiple traits (sickle-cell disease)
polygenic inheritance
multiple genes –> single trait
epistasis
the expression of one gene is masked, inhibited or suppressed by the expression of one or more other genes
