Question

Define aneuploidy . Name an allosomal hyperneuploidy condition and mention its characters.

Answer 1

• Aneuploidy refers to the condition in which an abnormal number of chromosomes is present within a cell (either 46 0r 47 chromosomes instead of the normal 46 chromosomes).
• An allosome is a chromosome that is different from the rest of the chromosomes (autosomes) in its size and structure (X and Y chromosomes).
• In hyperdiploidy, the number of chromosomes is higher than the normal (46) which is caused due to the disjunction at the time of meiosis and results in trisomy, etc. of a chromosome.
• In an allosomal hyperneuploid disorder, there is an increase in the number of either the X chromosome or the Y chromosome.
• For example, in Klinefelter’s syndrome, the karyotype of an individual is 44+XXY as an extra X chromosome is present in the male.
• Some common characters of this syndrome include infertility, high-pitched voice, gynecomastia, small-sized testicles, language and learning difficulties, etc.