Question

Which one is not related to chromosomal abnormality:
(a) Aneuploidy
(b) Euploidy
(c) Klinefelter’s syndrome
(d) AIDS

Answer 1

Chromosomal abnormalities also referred to as chromosomal disorders or chromosomal aberrations are caused due to absence or excess or abnormal arrangement of one or more chromosomes. These abnormalities affect the growth and development of the individual.

Complete answer:
Aneuploidy is due to the failure of the segregation of chromatids during the cell division cycle which results in a gain or loss of chromosome(s). Examples of aneuploidy are Trisomy of 21 (Down’s syndrome) and Klinefelter’s syndrome.
Euploidy is a condition in which a cell or an organism has more than a complete set of chromosomes. It occurs whenever a cell has a multiple of the haploid number of chromosomes.
Klinefelter’s syndrome is a genetic disorder caused due to the presence of an additional copy of the X chromosome which results in a karyotype of 47, XXY. A person suffering from this syndrome has an overall masculine development however feminine development (development of breast, Gynaecomastia) is also expressed. These individuals are sterile.
Acquired Immunodeficiency Syndrome(AIDS) is a viral syndrome caused by a retrovirus named human immunodeficiency virus(HIV). HIV attacks a specific type of immune system cell known as the CD4 helper cell or T cell and destroys it. This makes the immune system weak and makes it hard for the body to fight off infections and some types of cancers.

Additional information: Turner’s syndrome is also a case of Aneuploidy in which there is an absence of one of the X chromosomes which results in a karyotype of 45, X0. In such females, ovaries are sterile and rudimentary and they lack the development of secondary sexual characters.
So, the correct answer is ‘(d) AIDS’.

Note: Euploidy can also be referred to as polyploidy which is a phenomenon that happens due to the failure of cytokinesis after the telophase stage of cell division that results in an increase in a whole set of chromosomes in the organism.