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Haplogroup R-Z18
R-Z18 is a subclade of the R-U106 branch of Haplogroup R. It includes all men who have the single nucleotide polymorphism (SNP) designated Z18 in their Y chromosome. Z18, also called S493, is defined to be mutation in which the nucleotide at position 14,991,735 along the Y chromosome has mutated from guanine (G) to adenine (A). Z18 was discovered during Phase 3 of the 1000 Genomes Project, and entered on 16 August 2014 into the SNP database dbSNP at the National Center for Biotechnology Information as reference SNP cluster report rs767290651. R-U106 is one of the major sub groups of R1b in coastal Western Europe, but Z18 is only about 5-10% of U106. R-Z18 has its highest concentrations in Scandinavia, but is also found throughout areas of Germanic migration, including the Low Countries, Central Europe, and the British Isles. The likely Scandinavian origins of R-Z18 are bolstered by the dominance of Scandinavian individuals among ancient DNA samples. These consist of ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup
A haplotype is a group of alleles in an organism that are inherited together from a single parent, and a haplogroup (haploid from the el, ἁπλοῦς, ''haploûs'', "onefold, simple" and en, group) is a group of similar haplotypes that share a common ancestor with a single-nucleotide polymorphism mutation. More specifically, a haplogroup is a combination of alleles at different chromosomal regions that are closely linked and that tend to be inherited together. As a haplogroup consists of similar haplotypes, it is usually possible to predict a haplogroup from haplotypes. Haplogroups pertain to a single line of descent. As such, membership of a haplogroup, by any individual, relies on a relatively small proportion of the genetic material possessed by that individual. Each haplogroup originates from, and remains part of, a preceding single haplogroup (or paragroup). As such, any related group of haplogroups may be precisely modelled as a nested hierarchy, in which each set (hap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup R1b
Haplogroup R1b (R-M343), previously known as Hg1 and Eu18, is a human Y-chromosome haplogroup. It is the most frequently occurring paternal lineage in Western Europe, as well as some parts of Russia (e.g. the Bashkirs) and pockets of Central Africa (e.g. parts of Chad and among the Chadic-speaking minority ethnic groups of Cameroon). The clade is also present at lower frequencies throughout Eastern Europe, Western Asia, as well as parts of North Africa, South Asia and Central Asia. R1b has two primary branches: R1b1-L754 and R1b2-PH155. R1b1-L754 has two major subclades: R1b1a1b-M269, which predominates in Western Europe, and R1b1b-V88, which is today common in parts of Central Africa. The other branch, R1b2-PH155, is so rare and widely dispersed that it is difficult to draw any conclusions about its origins. It has been found in Bahrain, India, Nepal, Bhutan, Ladakh, Tajikistan, Turkey, and Western China. According to ancient DNA studies, most R1a and R1b lineages would hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single Nucleotide Polymorphism
In genetics, a single-nucleotide polymorphism (SNP ; plural SNPs ) is a germline substitution of a single nucleotide at a specific position in the genome. Although certain definitions require the substitution to be present in a sufficiently large fraction of the population (e.g. 1% or more), many publications do not apply such a frequency threshold. For example, at a specific base position in the human genome, the G nucleotide may appear in most individuals, but in a minority of individuals, the position is occupied by an A. This means that there is a SNP at this specific position, and the two possible nucleotide variations – G or A – are said to be the alleles for this specific position. SNPs pinpoint differences in our susceptibility to a wide range of diseases, for example age-related macular degeneration (a common SNP in the CFH gene is associated with increased risk of the disease) or nonalcoholic fatty liver disease (a SNP in the PNPLA3 gene is associated with incr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Y Chromosome
The Y chromosome is one of two sex chromosomes (allosomes) in therian mammals, including humans, and many other animals. The other is the X chromosome. Y is normally the sex-determining chromosome in many species, since it is the presence or absence of Y that determines the male or female sex of offspring produced in sexual reproduction. In mammals, the Y chromosome contains the gene SRY, which triggers male development. The DNA in the human Y chromosome is composed of about 59 million base pairs, making it similar in size to chromosome 19. The Y chromosome is passed only from father to son. With a 30% difference between humans and chimpanzees, the Y chromosome is one of the fastest-evolving parts of the human genome. The human Y chromosome carries an estimated 100–200 genes, with between 45 and 73 of these being protein-coding. All single-copy Y-linked genes are hemizygous (present on only one chromosome) except in cases of aneuploidy such as XYY syndrome or XXYY syndrome. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleotide
Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common nutrients by the liver. Nucleotides are composed of three subunit molecules: a nucleobase, a five-carbon sugar (ribose or deoxyribose), and a phosphate group consisting of one to three phosphates. The four nucleobases in DNA are guanine, adenine, cytosine and thymine; in RNA, uracil is used in place of thymine. Nucleotides also play a central role in metabolism at a fundamental, cellular level. They provide chemical energy—in the form of the nucleoside triphosphates, adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP) and uridine triphosphate (UTP)—throughout the cell for the many cellular func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guanine
Guanine () ( symbol G or Gua) is one of the four main nucleobases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine (uracil in RNA). In DNA, guanine is paired with cytosine. The guanine nucleoside is called guanosine. With the formula C5H5N5O, guanine is a derivative of purine, consisting of a fused pyrimidine-imidazole ring system with conjugated double bonds. This unsaturated arrangement means the bicyclic molecule is planar. Properties Guanine, along with adenine and cytosine, is present in both DNA and RNA, whereas thymine is usually seen only in DNA, and uracil only in RNA. Guanine has two tautomeric forms, the major keto form (see figures) and rare enol form. It binds to cytosine through three hydrogen bonds. In cytosine, the amino group acts as the hydrogen bond donor and the C-2 carbonyl and the N-3 amine as the hydrogen-bond acceptors. Guanine has the C-6 carbonyl group that acts as the hydrogen bond acceptor, while a group at N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenine
Adenine () ( symbol A or Ade) is a nucleobase (a purine derivative). It is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters G–C–A–T. The three others are guanine, cytosine and thymine. Its derivatives have a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate (ATP) and the cofactors nicotinamide adenine dinucleotide (NAD), flavin adenine dinucleotide (FAD) and Coenzyme A. It also has functions in protein synthesis and as a chemical component of DNA and RNA. The shape of adenine is complementary to either thymine in DNA or uracil in RNA. The adjacent image shows pure adenine, as an independent molecule. When connected into DNA, a covalent bond is formed between deoxyribose sugar and the bottom left nitrogen (thereby removing the existing hydrogen atom). The remaining structure is called an ''adenine residue'', as part of a larger molecule. Adenosine is ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1000 Genomes Project
The 1000 Genomes Project (abbreviated as 1KGP), launched in January 2008, was an international research effort to establish by far the most detailed catalogue of human genetic variation. Scientists planned to sequence the genomes of at least one thousand anonymous participants from a number of different ethnic groups within the following three years, using newly developed technologies which were faster and less expensive. In 2010, the project finished its pilot phase, which was described in detail in a publication in the journal ''Nature''. In 2012, the sequencing of 1092 genomes was announced in a ''Nature'' publication. In 2015, two papers in ''Nature'' reported results and the completion of the project and opportunities for future research. Many rare variations, restricted to closely related groups, were identified, and eight structural-variation classes were analyzed. The project unites multidisciplinary research teams from institutes around the world, including China, Ita ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic Modal Haplotype
In human genetics, the Atlantic modal haplotype (AMH) or haplotype 15 is a Y chromosome haplotype of Y-STR microsatellite variations, associated with the Haplogroup R1b. It was discovered prior to many of the SNPs now used to identify subclades of R1b and references to it can be found in some of the older literature. It corresponds most closely with subclade R1b1a2a1a(1) 11 The AMH is the most frequently occurring haplotype amongst human males in Atlantic Europe. It is characterized by the following marker alleles: *DYS388 12 *DYS390 24 *DYS391 11 *DYS392 13 *DYS393 13 *DYS394 14 (also known as DYS19) It reaches the highest frequencies in the Iberian Peninsula, in Great Britain and Ireland. In the Iberian Peninsula it reaches 70% in Portugal as a whole, more than 90% in NW Portugal and nearly 90% in Galicia (NW Spain), while the highest value is to be found among Spain and the Basques. One mutation in either direction, would be AMH 1.15+. The AMH 1.15 set of haplotypes is also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genealogical DNA Test
A genealogical DNA test is a DNA-based test used in genetic genealogy that looks at specific locations of a person's genome in order to find or verify ancestral genealogical relationships, or (with lower reliability) to estimate the ethnic mixture of an individual. Since different testing companies use different ethnic reference groups and different matching algorithms, ethnicity estimates for an individual vary between tests, sometimes dramatically. Three principal types of genealogical DNA tests are available, with each looking at a different part of the genome and being useful for different types of genealogical research: autosomal (atDNA), mitochondrial (mtDNA), and Y-DNA. Autosomal tests may result in a large number of DNA matches to both males and females who have also tested with the same company. Each match will typically show an estimated degree of relatedness, i.e., a close family match, 1st-2nd cousins, 3rd-4th cousins, etc. The furthest degree of relationship is u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Y-chromosome DNA Haplogroup
In human genetics, a human Y-chromosome DNA haplogroup is a haplogroup defined by mutations in the non- recombining portions of DNA from the male-specific Y chromosome (called Y-DNA). Many people within a haplogroup share similar numbers of short tandem repeats (STRs) and types of mutations called single-nucleotide polymorphisms (SNPs). The human Y-chromosome accumulates roughly two mutations per generation. "one mutation in every 30 million base pairs" Y-DNA haplogroups represent major branches of the Y-chromosome phylogenetic tree that share hundreds or even thousands of mutations unique to each haplogroup. The Y-chromosomal most recent common ancestor (Y-MRCA, informally known as Y-chromosomal Adam) is the most recent common ancestor (MRCA) from whom all currently living humans are descended patrilineally. Y-chromosomal Adam is estimated to have lived roughly 236,000 years ago in Africa. By examining other bottlenecks most Eurasian men (men from populations outside of Afri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Europe
Prehistoric Europe is Europe with human presence but before the start of recorded history, beginning in the Lower Paleolithic. As history progresses, considerable regional irregularities of cultural development emerge and increase. The region of the eastern Mediterranean is, due to its geographic proximity, greatly influenced and inspired by the classical Middle Eastern civilizations, and adopts and develops the earliest systems of communal organization and writing. The Histories of Herodotus (from around 440 BC) is the oldest known European text that seeks to systematically record traditions, public affairs and notable events. Overview Widely dispersed, isolated finds of individual fossils of bone fragments (Atapuerca, Mauer mandible), stone artifacts or assemblages that suggest that during Lower Paleolithic, spanning from 3 million until 300,000 years ago, palaeo-human presence are rare and typically separated by thousands of years. The karstic region of the Atapuerca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
