Question

A 10 year old patient is found to have the following clinical features: Slanting eyes with epicanthic fold of skin in the eyelid,hypertelorism,dysplastic ears,mongoloid face and protruding tongue.
The chromosomal condition of the above syndrome is
A. Autosomal aneuploidy
B. Allosomal hyper aneuploidy
C. Allosomal hyper aneuploidy
D. Autosomal partial deletion

Answer 1

Hint: In order to deduce a correct answer, try to understand what is the basic meaning of terms like autosome and allosome. In addition to these terms, try to understand the basic definition of aneuploidy. For example, autosomal means relating to all the chromosomes except the allosomes. By joining it with the word aneuploidy, you will be able to arrive at a correct answer.

Complete answer:
To know the correct answer, we must know the definition of each of these words. Aneuploidy is defined as having either more or less chromosome than the exact number. By autosomal aneuploidy, we mean changes in those chromosomes that are not sex chromosomes. Allosomal hyperaneuploidy refers to the change in the number of allosomes or sex chromosomes preferably an increase in the number of sex chromosomes is termed as Allosomal hyperaneuploidy.On the other hand, Allosomal hypoaneuploidy refers to a decrease in the number of sex chromosomes. When a part of an autosome gets deleted, it is called Autosomal partial deletion. The above syndrome mentioned shows characteristics similar to that of Down syndrome. Down syndrome mostly arises due to a Trisomy of chromosome 21. Here a child is born with an extra copy of chromosome 21 thus causing down syndrome with the above-mentioned symptoms.

Thus, the correct answer is option A Autosomal aneuploidy.

Note:
Trisomy 21 is the most common aneuploidy found in humans. Maternal age is the only factor that affects the chance of having an affected baby that results from nondisjunction or mosaicism.