In
genetics, a subclade is a subgroup of a
haplogroup.
Naming convention
Although
human mitochondrial DNA (mtDNA) and
Y chromosome DNA (Y-DNA) haplogroups and subclades are named in a similar manner, their names belong to completely separate systems.
[
]
mtDNA
mtDNA haplogroups are defined by the presence of a series of single-nucleotide polymorphism (SNP) marker
The term Marker may refer to:
Common uses
* Marker (linguistics), a morpheme that indicates some grammatical function
* Marker (telecommunications), a special-purpose computer
* Boundary marker, an object that identifies a land boundary
* Marke ...
s in the hypervariable regions and the coding region
The coding region of a gene, also known as the coding sequence (CDS), is the portion of a gene's DNA or RNA that codes for protein. Studying the length, composition, regulation, splicing, structures, and functions of coding regions compared to no ...
of mitochondrial DNA
Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial D ...
. They are named with the capital letters A through Z, with further subclades named using numbers and lower case letters.
Y-DNA
Y-DNA haplogroups are defined by the presence of a series of SNP markers on the Y chromosome. Subclades are defined by a ''terminal SNP'', the SNP furthest down in the Y chromosome phylogenetic tree.
Human Y-DNA
The Y Chromosome Consortium (YCC) developed a system of naming major human Y-DNA haplogroups with the capital letters A through T, with further subclades named using numbers and lower case letters (YCC longhand nomenclature). YCC shorthand nomenclature names Y-DNA haplogroups and their subclades with the first letter of the major Y-DNA haplogroup followed by a dash and the name of the defining terminal SNP. Y-DNA haplogroup nomenclature is changing over time to accommodate the increasing number of SNPs being discovered and tested, and the resulting expansion of the Y chromosome phylogenetic tree. This change in nomenclature has resulted in inconsistent nomenclature being used in different sources.
See also
*Clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...
* Cladistics
*Haplotype
A haplotype ( haploid genotype) is a group of alleles in an organism that are inherited together from a single parent.
Many organisms contain genetic material ( DNA) which is inherited from two parents. Normally these organisms have their DNA or ...
References
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Genetics
Genetic genealogy