Which one of the following statements is the correct fact about human…

The correct answer is Option (3) → Less than 2 percent of the genome codes for proteins.

(1) The average gene consists of 30000 bases. — Incorrect. The average gene has about 3000 bases. The figure 30,000 is the estimated total number of genes.

(2) The functions are unknown for less than 20 percent of the discovered genes. — Incorrect. The functions are unknown for over 50 percent of the discovered genes.

(3) Less than 2 percent of the genome codes for proteins. — Correct. Most of the genome is non-coding. A very large part of it is repeated sequences.

(4) Chromosome Y has the most genes (2968), and 1 has the fewest (231). — Incorrect. The two are reversed. Chromosome 1 has the most genes (2968), and the Y has the fewest (231).

Note: A similar question was also asked in CUET (UG) 2026 on 24-05-2026 (Slot 2), and in CUET (UG) 2025 on 22-05-2025 (Slot 2).

NCERT Extract:
Salient Features of Human Genome – “… (ii) The average gene consists of 3000 bases, but sizes vary greatly, with the largest known human gene being dystrophin at 2.4 million bases. (iii) The total number of genes is estimated at 30,000– much lower than previous estimates of 80,000 to 1,40,000 genes. Almost all (99.9 per cent) nucleotide bases are exactly the same in all humans. (iv) The functions are unknown for over 50 per cent of the discovered genes. (v) Less than 2 per cent of the genome codes for proteins. (vi) Repeated sequences make up very large portion of the human genome. (vii) Repetitive sequences are stretches of DNA sequences that are repeated many times, sometimes hundred to thousand times. They are thought to have no direct coding functions, but they shed light on chromosome structure, dynamics and evolution. (viii) Chromosome 1 has most genes (2968), and the Y has the fewest (231).”