Question

Following features belong to which syndrome?
(I) Furrowed tongue
(II) Palm is broad with characteristic palm crease.
(III) Physical and mental retardation
(IV) Short statured with small round head.

• A. Down's syndrome
• B. Turner's syndrome
• C. Klinefelter's syndrome
• D. Cri du chat syndrome

Answer 1

Answer: (A)

Down's syndrome is due to an extra chromosome number $21.$ The patient's cells have 3 copies of 21st chromosome (Trisomy 21) instead of homologous pair. It occurs due to failure of separation of homologous chromosomes or non-disjunction during meiosis (gamete formation). Symptoms of Down's syndrome:
$\left(a\right)$ Patients show Mental retardation
$\left(b\right)$ Due to poor skeletal development, they have short stature and relatively small skull
$\left(c\right)$ Their face is typically flat with rounded flat nose
$\left(d\right)$ They have an open mouth, protruding tongue and a high arched palate.
$\left(e\right)$ Most children show typical facial features with a fold of skin (epicanthal skin fold) over the inner corner of the eye. This results in downward slanting of eyelids.
$\left(f\right)$ They have flat hand with characteristic crease which runs all the way across the palm (Simian crease).