<unk>  (UTS) is a syndrome that was discovered by the Turkish evolutionary biologist Üner<unk> . People affected by UTS walk with a quadrupedal locomotion and often have severe learning disabilities.<unk>  postulated that this is an example of "reverse evolution" (atavism). The proposed syndrome was featured in the 2006 BBC2 documentary The Family That Walks On All Fours.
Uner Tan syndrome
Brunner syndrome
Horner's syndrome
Nance–Horan syndrome
Gougerot–Blum syndrome
Villaret's syndrome
Larsen syndrome
Van Wyk and Grumbach syndrome