|
Y-chromosomal Aaron is the name given to the hypothesized most recent common ancestor of many of the patrilineal Jewish priestly caste known as ''Kohanim'' (singular "Kohen", "Cohen", or ''Kohane''). In the Torah, this ancestor is identified as Aaron, the brother of Moses. The hypothetical most recent common ancestor was therefore dubbed "Y-chromosomal Aaron", by analogy to Y-chromosomal Adam. The original scientific research was based on the discovery that a majority of present-day Jewish Kohanim either share, or are only one step removed from, a pattern of values for 6 Y-STR markers, which researchers named the Cohen Modal Haplotype (CMH). Later research, using a larger number of Y-STR markers to gain higher resolution more specific genetic signatures, has indicated that about half of contemporary Jewish Kohanim, who share Y-chromosomal haplogroup J1c3 (also called J-P58), appear to be closely related. A further approximately 15% of Kohanim fall into a second distinct group, sharing a different but similarly tightly related ancestry. This second group fall under haplogroup J2a (J-M410). A number of other smaller lineage groups are also observed. The most recent Molecular phylogenetic research for haplogroup J-M267 places the "Extended Cohen Modal Haplotype" within subhaplogroup ZS222 (age estimate 2638-3280 yBP). ==Background== Although membership in the Jewish community has, since at least the second century CE, been passed maternally (see: Who is a Jew?), tribal identity, and membership in the group that originally comprised the Jewish priesthood (''Cohen'' or ''Kohen''; plural: ''Cohanim'' or ''Kohanim''), has been patrilineal. Modern Kohanim claim descent from a biblical person, Aaron, brother of Moses, in the direct lineage from Levi, the patriarch of the Tribe of Levi, great grandson of Abraham, according to the tradition codified in the Tanakh (שמות / Sh'mot/Exodus 6). DNA testing is aiding scholars to trace the lineages found among modern Jewish populations, including contemporary Cohen families, to decipher origins of the people groups who were joined to the ancient Israelites and to identify genetic admixture and genetic drift. For human beings, the normal number of chromosomes is 46, of which 23 are inherited from each parent. Two chromosomes, the X chromosome and Y chromosome, determine sex. Women have two X chromosomes, one inherited from their mother, and one inherited from their father. Men have an X chromosome inherited from their mother, and the Y chromosome inherited from their father. Males who share a common patrilineal ancestor also share a Y chromosome, diverging only with respect to accumulated mutations. Since Y-chromosomes are passed from father to son, all Kohanim men should theoretically have almost identical Y chromosomes; this can be tested with a genealogical DNA test. As the rate that mutations accumulate on the Y chromosome is relatively constant, scientists can estimate the elapsed time since two men had a common ancestor. (See molecular clock.) "The Samaritan M267 lineages differed from the classical Cohen modal haplotype at DYS391, carrying 11 rather than 10 repeats", as well as, have a completely different haplogroup, which should have been "J1". Samaritan Kohanim descend from a different patrilineal family line, having haplogroup E1b1b1a (M78) (formerly E3b1a). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Y-chromosomal Aaron」の詳細全文を読む スポンサード リンク
|