Genetic forms of breast cancer account for the minority of cases. Males who carry a susceptibility gene for some forms of genetic breast cancer can be at risk, themselves, for cancer. Cance r of the lower digestive tract. Hereditary and non-hereditary forms exist. Persons with color blindness have difficulty telling the difference between red, green, and blue colors.
Inheritance is autosomal recessive.
The incidence is 1 in 2,000 among Northern Europeans. Down syndrome One of the most common chromosomal disorders with the incidence being 1 in 1200. The most common inherited form of mental retardation. It also includes specific physical features recognizable to trained clinicians. The inheritance is X-linked with an incidence of 1 in 750 in males.