Post by Noah on Jul 31, 2011 19:57:05 GMT -5
Uniparental markers
First, there are uniparental markers. This is genetic material that is transmitted from one parent to his or her children in a heritable fashion. Uniparental markers include Y DNA and mtDNA.
Y DNA
Y DNA is also referred to in the scientific literature as "paternal DNA" because it's only passed down from fathers to their sons but not to their daughters. This "Y" that is passed down from father to son is a sex chromosome. I'm sure you've heard the famous expression that "only men have a Y chromosome". Well, this is what it means. And it is this Y chromosome that also determines the gender of a child. If a child has a Y chromosome (barring abnormal conditions like hermaphroditism, of course), then he is a boy; if not, she is a girl. Thus, the Y chromosome can be used to trace the paternal ancestry of a person.
Examples of Y DNA/paternal haplogroups that are common in Hamitic populations include E1b1b, which is the signature Hamitic sub-haplogroup (actually, haplogroup E as a whole was originally a Hamitic clade).
mtDNA
There is also mtDNA, which geneticists refer to as "maternal DNA" because it is only passed down from mothers to all of their biological children (both girls and boys this time). However, only daughters can in turn transmit this "mitochondrial DNA" to their own children (that's what the "m" in mtDNA stands for). Sons can't transmit mtDNA to their own children. It's a bit like a mother handing over two precious family heirlooms to her two children, one to her daughter and one to her son, but telling them that, by tradition, only girls are allowed to hand over the heirloom that they received to their own future children. Thus, analysing the mtDNA of a woman or a man allows us to find out the haplogroups to which his or her female ancestors belonged. This is also known as a person's "maternal ancestry" or "maternal heritage".
Examples of mtDNA/maternal haplogroups that are common in Hamitic populations include M1, R0a, HV1, U6, H and I -- all Eurasian clades. The proto-Eurasian macrohaplogroup L3, from which all Eurasian clades descend, is also fairly common.
Below are charts from the International Society of Genetic Genealogy (ISOGG) that illustrate both the paternal and maternal lines of ancestry.
Path of Y-DNA - Male Paternal Line Only
Path of mtDNA - Female Maternal Line Only
First, there are uniparental markers. This is genetic material that is transmitted from one parent to his or her children in a heritable fashion. Uniparental markers include Y DNA and mtDNA.
Y DNA
Y DNA is also referred to in the scientific literature as "paternal DNA" because it's only passed down from fathers to their sons but not to their daughters. This "Y" that is passed down from father to son is a sex chromosome. I'm sure you've heard the famous expression that "only men have a Y chromosome". Well, this is what it means. And it is this Y chromosome that also determines the gender of a child. If a child has a Y chromosome (barring abnormal conditions like hermaphroditism, of course), then he is a boy; if not, she is a girl. Thus, the Y chromosome can be used to trace the paternal ancestry of a person.
Examples of Y DNA/paternal haplogroups that are common in Hamitic populations include E1b1b, which is the signature Hamitic sub-haplogroup (actually, haplogroup E as a whole was originally a Hamitic clade).
mtDNA
There is also mtDNA, which geneticists refer to as "maternal DNA" because it is only passed down from mothers to all of their biological children (both girls and boys this time). However, only daughters can in turn transmit this "mitochondrial DNA" to their own children (that's what the "m" in mtDNA stands for). Sons can't transmit mtDNA to their own children. It's a bit like a mother handing over two precious family heirlooms to her two children, one to her daughter and one to her son, but telling them that, by tradition, only girls are allowed to hand over the heirloom that they received to their own future children. Thus, analysing the mtDNA of a woman or a man allows us to find out the haplogroups to which his or her female ancestors belonged. This is also known as a person's "maternal ancestry" or "maternal heritage".
Examples of mtDNA/maternal haplogroups that are common in Hamitic populations include M1, R0a, HV1, U6, H and I -- all Eurasian clades. The proto-Eurasian macrohaplogroup L3, from which all Eurasian clades descend, is also fairly common.
Below are charts from the International Society of Genetic Genealogy (ISOGG) that illustrate both the paternal and maternal lines of ancestry.
Path of Y-DNA - Male Paternal Line Only
Path of mtDNA - Female Maternal Line Only