Amniocentesis is not legally used to test:

The correct answer is Option (2) → Sex of the foetus

In amniocentesis, a little of the amniotic fluid around the developing foetus is taken out. The foetal cells and the substances dissolved in it are studied to find genetic disorders.

Option (1) Haemophilia — Legally tested by amniocentesis. Haemophilia is a sex-linked recessive disease in which the blood does not clot properly, so a small cut can bleed for a long time. Being a genetic disorder, it may be checked by this test.

Option (2) Sex of the foetus — Not legally tested by amniocentesis. The chromosomes of the foetal cells also show the sex of the child. Its misuse led to the killing of female foetuses, so in India there is a statutory ban on amniocentesis for sex-determination. Statutory means made by law.

Option (3) Thalassemia — Legally tested by amniocentesis. Thalassemia is an autosomal recessive blood disorder in which too little globin is made, so the person becomes anaemic. As a genetic disorder, it may be checked by this test.

Option (4) Sickle cell anemia — Legally tested by amniocentesis. In sickle-cell anaemia one amino acid of haemoglobin is changed (glutamic acid to valine), and the red blood cells become sickle-shaped. It is a genetic disorder, so the test may look for it.

NCERT Extract:
Reproductive Health – Problems and Strategies – “… Statutory ban on amniocentesis for sex-determination to legally check increasing menace of female foeticides, massive child immunisation, etc., are some programmes that merit mention in this connection. In aminocentesis some of the amniotic fluid of the developing foetus is taken to analyse the fetal cells and dissolved substances. This procedure is used to test for the presence of certain genetic disorders such as, down syndrome, haemoplilia, sickle-cell anemia, etc., determine the survivability of the foetus.”