Match the LIST-I with LIST-II
| LIST-I | LIST-II |
|---|---|
| Genetic disorders | Features |
| A. Haemophilia | I. Phenylalanine is not converted into tyrosine |
| B. Sickle-cell anaemia | II. Mutation or deletion which results in reduced rate of synthesis of one of the globin chains |
| C. Phenylketonuria | III. A single protein is absent that is part of the cascade of protein involved in blood clotting |
| D. Thalassemia | IV. Base substitution at the sixth codon of β globin gene from GAG to GUG |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → A - III, B - IV, C - I, D - II
(A) Haemophilia — this matches (III) A single protein is absent that is part of the cascade of protein involved in blood clotting. Blood clotting needs a chain (cascade) of proteins. When one of them is missing, the blood does not clot, and even a small cut keeps bleeding. It is a sex-linked recessive disease.
(B) Sickle-cell anaemia — this matches (IV) Base substitution at the sixth codon of β globin gene from GAG to GUG. This single base change puts valine in place of glutamic acid at the sixth position of the β globin chain. The changed haemoglobin makes red blood cells take a sickle shape at low oxygen.
(C) Phenylketonuria — this matches (I) Phenylalanine is not converted into tyrosine. The enzyme that converts the amino acid phenylalanine into tyrosine is missing. So phenylalanine builds up and harms the brain. It is an inborn error of metabolism.
(D) Thalassemia — this matches (II) Mutation or deletion which results in reduced rate of synthesis of one of the globin chains. Too little of one globin chain gives abnormal haemoglobin and anaemia. It is a quantitative problem (too little globin), while sickle-cell anaemia is a qualitative one (a wrongly made globin).