World health report

Conquering suffering, enriching humanity

Human genetics, hereditary diseases and birth defects

In typical developed societies, congenital and genetic disorders are second only to perinatal factors as the most common cause of infant and childhood death. Some of these disorders are hereditary, including thalassaemia and sickle cell disorder. Almost 70% of cases of the latter occur in sub-Saharan Africa.

Cystic fibrosis occurs worldwide. Life expectancy in developed countries for children with the disease has improved however, thanks to medical advances; but up to 95% of cases in Latin America, for example, are never diagnosed.

Some 420 000 people in the world are estimated to have haemophilia. Until recently, the foremost cause of death was haemorrhage; in the past decade, this has been overtaken by infections as the side-effects of treatment, including HIV/AIDS and liver disease secondary to hepatitis.

About 3 million fetuses and infants a year are born with major congenital malformations; the causes of about 70% remain unknown.