Q.
"They have raised cheek bones, oblique eyes and yellowish skin colours". Here they refers to
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AIIMSAIIMS 2000Principles of Inheritance and Variation
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Solution:
"They have raised cheek bones, oblique eyes and yellowish skin colours". Here they refer to mongoloids. This syndrome was described by Langdon-Down in 1866 and was popularly called mongolian idiots or Down’s syndrome. Trisomy 21 is responsible for it. Phenotypic abnormalities associated with this syndrome resembles mongoloidsthus called mongolian idiots. The features are slant of eyes, thick tongue, sagging mouth, unusual palm and feet, obesity and slow mental growth. The life expectancy of these is about 8 to 12 years.