Question

Give 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 = 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. 99.9 nucleotide bases are identical in all people. 0.1 is what makes each of us unique.

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

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

g. Less than 2 of the genome codes for proteins.

h. Repeated sequences make up very large portion of human genome. Repetitive sequences are stretched of DNA sequences that are repeated many times. They have no direct coding functions, but they shed light on chromosome structure, dynamics and evolution.

i. About 1.4 million locations where single-base DNA differences (SNPs- Single nucleotide polymorphism or 'snips') occur in humans.