A hand book of life sciences/CLASSICAL GENETICS

AUTOSOMAL DOMINANT
Ex: Huntington's chorea,Neurofibromatosis,Achondroplasia,Familial hypercholesterolemia
 * Each affected person has an affected parents.
 * It occurs in every generation.
 * There is male to male transmission.

AUTOSOMAL RECESSIVE
Ex:Sickle cell anemia,Cystic fibrosis,Phenylketonuria,Tay-Sachs disease
 * Most affected individuals have unaffected parents.
 * Both parents of unaffected persons are carriers but offsprings are affected.
 * Trait often skips generations.

X-LINKED DOMINANT
Ex:Hypophatemic rickets (vitamin-D resistant rickets), Ornithine Transcarbamylase deficiency
 * Females are more frequently affected from mothers.
 * Affected females comes from affected mothers or fathers.
 * If the male is affected then all of his daughters would be affects but non of his sons are affected.
 * If the female is affected then about half of her sons are affected.
 * It present in each generation.

X-LINKED RECESSIVE
Ex:Hemophilia A,Duchenne Muscular Dystrophy,Colour blindness, Night blindness,Fragile X-syndrome
 * Most affected individuals are male.
 * Affected males comes from mother who are affected or carriers.
 * Affected females comes affected father and affected or carrier mother.
 * Affected males present in each generation.

Y-LINKED INHERITANCE
Ex:Flatfoot and hair loss
 * It is also known as holandric inheritance.
 * Affects only Males.
 * Affected males always have an affected father.
 * If the fathers will affected,all of his sons will be affected.

MITOCHONDRIAL DISORDERS
Ex:Mitochondrial myopathy, Diabetes mellitus and deafness(DAD)
 * This inheritance can affect both males and females.But only passed on by females.
 * It can appear in every generation.