J1 (Y-DNA)

Haplogroup J1, more fully Y DNA haplogroup J-M267, is a Y chromosome haplogroup found in the Middle East. This means it is found in a group of descendants from a single common ancestor in the father's line. It carries a mutation on the Y chromosome known as M267. This type of mutation is called a SNP, or a single nucleotide polymorphism, a change at one position in a gene's DNA. 

Y chromosomes are passed down from father to son without changing, so an SNP like this shows common ancestry.Di Giacomo F. et al 2004. Y chromosomal haplogroup J as a signature of the post-neolithic colonization of Europe. Human Genetics 115 (5): 357–371. 

The origin of this mutation was between 4,000 and 24,000 years ago.

This mutation followed a previous mutation, which created the haplogroup known as haplogroup J-P209 or simply haplogroup J, and so this makes the Y chromosome the "child" of the older version of the Y chromosome. Haplogroup J arose from a mutation which occurred about 31,700 years ago in Southwest Asia.Y-DNA haplogroup J 

References

Category:Chromosomes
Category:DNA