health

Researchers estimate that achondroplasia occurs in one in every 15,000 to
40,000 live births. About 20 percent of cases are children who have one
parent with achondroplasia; however, 75–80 percent of cases involve new
mutations of the gene responsible for the disorder.
These new mutations are more likely to occur in
the sperm of fathers over 35; the mother’s age does
not matter, as far as is presently known.
The disorder affects both sexes and all races
equally.
The average adult height of people with achondroplasia
is 4 feet 4 inches (1.3 meters) for men and
4 feet one-half inch (1.24 m) for women. The
shortest living person with achondroplasia as of
2008 was Jyoti Amge, a teenager from Nagpur,
India, who stands 23 inches (58 centimeters) tall
and weighs 11 pounds (5 kilograms).