An early settler of a community passes an abnormal gene on to the next generation. Usually in those who carry an autosomal abnormal gene, the disease is not expressed. However, if a baby inherits an abnormal gene from each parent, he or she inherits the disease. These diseases are known as autosomal recessive disorders and include many of the metabolic disorders. Awareness of genetic diseases in Amish and Mennonite populations has grown for several reasons, often giving rise to the perception that genetic disorders are occurring here with alarming frequency.
Most recessive disorders related to the founder effect reach a plateau in frequency.
Disorders such as maple syrup disease or gluteric aciduria 1 will continue to occur in this community at an estimated carrier rate of 1 in 10 and 1 in 15 respectively. Awareness of genetic diseases in this community has grown in part because children with these disorders are now diagnosed and treated - that is the Clinic's mission. Studies of modern genetics have been advanced due to the willingness of many Amish and Mennonite families to share their histories with those committed to the science over the last fifty years. We owe these families gratitude for their contribution to medical science that gives hope to all of us.