Question

List the salient features of human genome.

Answer 1

Salient features of Human Genome:

a. Human genome contains 3164.7 million nucleotide bases.

b. Total number of genes are about 30,000.

c. Average gene consists of 3000 bases but sizes vary. Largest known human gene (dystrophin on X-chromosome) contains 2.4 million bases.

d. About 99.9% nucleotide bases are identical in all people. It is that 0.1% which makes each one unique.

e. Functions of over 50 of discovered genes are unknown.

f. Chromosome I has most genes (2968) and Y has the least genes (231).

g. Repetitive sequences are stretched of DNA sequences that are repeated many times. They make the largest portion of DNA. They have no direct coding functions but they shed light on chromosome structure, dynamics and evolution.

h. There are about 1.4 million locations where single-base DNA differences (SNPs- Single nucleotide polymorphism) occur in humans.