A new syndrome with quadrupedal gait, primitive speech, and severe mental retardation as a live model for human evolution

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Tan U.

INTERNATIONAL JOURNAL OF NEUROSCIENCE, cilt.116, sa.3, ss.361-369, 2006 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 116 Konu: 3
  • Basım Tarihi: 2006
  • Doi Numarası: 10.1080/00207450500455330
  • Sayfa Sayıları: ss.361-369


The author has discovered a new syndrome with quadrupedal gait, flexed head and body, primitive speech, severe mental retardation, and mild cerebellar signs with a disturbed conscious experience. This syndrome was exhibited by 5 of 19 children from a consanguineous family. The pedigree demonstrated a typical autosomal-recessive inheritance. The genetic nature of this syndrome suggests a backward stage in human evolution, which is most probably caused by a genetic mutation, rendering, in turn, the transition from quadrupedality to bipedality. This would then be consistent with theories of punctuated evolution. On the other hand, the extensor motor system causing a resistance of the body against the gravity may actually be subjected to evolutionary forces. This new syndrome may be used as a live model for human evolution.