Question

Which list contains only chromosomal disorders?

Options

• Down's syndrome, Turner's syndrome, Klinefelter's syndrome

• Turner's syndrome, Haemophilia, Sickle-cell anaemia

• Haemophilia, Thalassaemia, Sickle-cell anaemia

• Down's syndrome, Colour blindness, PKU

Answer 1

Down's syndrome, Turner's syndrome, and Klinefelter's syndrome are all chromosomal disorders caused by numerical or structural chromosome abnormalities. They are not caused by single-gene mutations like the Mendelian disorders.