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A Reverse Genetic Approach to Test Functional Redundancy During Embryogenesis
Published on: August 11, 2010
Evidence for "Uner Tan Syndrome" as a human model for reverse evolution.
1Cukurova University, Medical School, Department of Physiology, Adana, Turkey. unertan@cu.edu.tr
The International Journal of Neuroscience
|December 6, 2006
Summary
Uner Tan Syndrome research in a second family reveals evidence of reverse evolution, including quadrupedality and primitive mental abilities. This suggests a single gene influences multiple traits, impacting human evolution.
Area of Science:
- Genetics
- Evolutionary Biology
- Neurology
Background:
- Uner Tan Syndrome (UTS) is a rare human genetic disorder.
- Previous studies suggested a single gene mutation as the cause.
- The syndrome is characterized by distinct physical and cognitive traits.
Purpose of the Study:
- To investigate a second family with Uner Tan Syndrome.
- To explore evidence for reverse evolution in affected individuals.
- To further elucidate the genetic and developmental underpinnings of UTS.
Main Methods:
- Clinical examination of affected individuals in a second family.
- Magnetic Resonance Imaging (MRI) to assess brain structure, particularly cerebellar atrophy.
- Behavioral observation and analysis of gait, limb ratios, and cognitive abilities.
Main Results:
- No significant cerebellar atrophy was observed, except for mild vermial atrophy in some individuals.
- Evidence supporting reverse evolution was found: habitual quadrupedality, primitive mental abilities, curved fingers during wrist-walking, and ape-like arm-to-leg ratios.
- Individuals were raised separately, ruling out socio-cultural imitation for quadrupedal gait.
Conclusions:
- The findings challenge the notion of cerebellar atrophy as the primary pathology in UTS.
- The study provides evidence for a single gene controlling multiple behavioral traits, supporting the single gene theory.
- Results align with the psychomotor theory and the co-evolution of the human mind and motor system, expressed through language.
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