The Vadoma people suffer from a rare genetic setting called ectrodactyly. A substantial minority of Vadoma has this condition known called Ectrodactyly in which the middle three toes are absent and the two outer ones are turned in, resulting in the tribe being known as the “two-toed” or “ostrich-footed” tribe.
Ectrodactyly is an inherited dominant genetic mutation. Some have theorized that the mutation may have adaptive benefit which help in tree climbing.
It is on record that those with the condition are not handicapped and well-integrated into the tribe.
Ectrodactyly occurs at lower rates throughout the world and can be caused by a number of human gene defects, a common one being a mutation of the 7th chromosome. It is also associated with hearing loss. Though ectrodactyly itself is fairly rare, occurring in 1 in 90:000 births, limb defects occur in roughly 1 in 1000 births, only slightly less than the rate of identical twin.
The condition prevails because of a small genetic pool among the Vadoma and is propagated by the tribal law that forbids members to marry outside the group.
The Vadoma people, also known as the Bantwana tribe, which means children/descendants, are a tribe living in the north of Zimbabwe, primarily in the Urungwe and Sipolilo districts on the Zambezi river valley. They are the only traditional hunter-gatherers indigenous to Zimbabwe and famous for the inherited ectrodactyly existing among some Vadoma families.
The Vadoma speak the Dema language , closely related to the dominant Shona language of Zimbabwe and highly comprehensible to Korekore and Tande Shona dialects. Living alongside Shona and Kunda people in Kanyemba, they also speak Korekore Shona and Kunda .
Due to the Vadoma tribe’s isolation, they have developed and maintained ectrodactyly, and their comparatively small gene pool has resulted in the condition being much more frequent than elsewhere. The Eastern Shona Kalanga of the Kalahari Desert also have a number of members with ectrodactyly and may be related.
Wiki, Zambianobserver.com and atlasobscura.com are majors source for this write-up.
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