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Genetic Studies On Sri Lankan Tamils
Although Sri Lankan Tamils are culturally and linguistically distinct, genetic studies indicate that they are closely related to other ethnic groups in the island while being related to the Indian Tamils from South India and Bengalis from the East India as well. There are various studies that indicate varying degrees of connections between Sri Lankan Tamils, Sinhalese and Indian ethnic groups. Study by Dr. Gautam K. Kshatriya According to a genetic admixture study by Dr. Gautam K. Kshatriya in 1995, the Sri Lankan Tamil are closely related to the Sinhalese who are closely related to Indian Tamils. Kshatriya found the Sri Lankan Tamils to have a greater contribution from the Sinhalese of Sri Lanka (55.20% +/- 9.47) while the Sinhalese had the greatest contribution from South Indian Tamils (69.86% +/- 0.61), followed by Bengalis from the East India (25.41% +/- 0.51). With both the Sri Lankan Tamils and Sinhalese in the island sharing a common gene pool of 55%. They are farthest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sri Lankan Tamils
Sri Lankan Tamils ( or ), also known as Ceylon Tamils or Eelam Tamils, are Tamils native to the South Asian island state of Sri Lanka. Today, they constitute a majority in the Northern Province, live in significant numbers in the Eastern Province and are in the minority throughout the rest of the country. 70% of Sri Lankan Tamils in Sri Lanka live in the Northern and Eastern provinces. Modern Sri Lankan Tamils descend from residents of the Jaffna Kingdom, a former kingdom in the north of Sri Lanka and Vannimai chieftaincies from the east. According to the anthropological and archaeological evidence, Sri Lankan Tamils have a very long history in Sri Lanka and have lived on the island since at least around the 2nd century BCE. The Sri Lankan Tamils are mostly Hindus with a significant Christian population. Sri Lankan Tamil literature on topics including religion and the sciences flourished during the medieval period in the court of the Jaffna Kingdom. Since the beginning o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alu Sequence
An Alu element is a short stretch of DNA originally characterized by the action of the ''Arthrobacter luteus (Alu)'' restriction endonuclease. ''Alu'' elements are the most abundant transposable elements, containing over one million copies dispersed throughout the human genome. ''Alu'' elements were thought to be selfish or parasitic DNA, because their sole known function is self reproduction. However, they are likely to play a role in evolution and have been used as genetic markers. They are derived from the small cytoplasmic 7SL RNA, a component of the signal recognition particle. ''Alu'' elements are highly conserved within primate genomes and originated in the genome of an ancestor of Supraprimates. ''Alu'' insertions have been implicated in several inherited human diseases and in various forms of cancer. The study of Alu elements has also been important in elucidating human population genetics and the evolution of primates, including the evolution of humans. Alu fam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup R1a (Y-DNA)
Haplogroup R1a, or haplogroup R-M420, is a human Y-chromosome DNA haplogroup which is distributed in a large region in Eurasia, extending from Scandinavia and Central Europe to southern Siberia and South Asia. While R1a originated c. 22,000 to 25,000 years ago, its subclade M417 (R1a1a1) diversified c. 5,800 years ago. The place of origin of the subclade plays a role in the debate about the origins of Proto-Indo-Europeans. The SNP mutation R-M420 was discovered after R-M17 (R1a1a), which resulted in a reorganization of the lineage in particular establishing a new paragroup (designated R-M420*) for the relatively rare lineages which are not in the R-SRY10831.2 (R1a1) branch leading to R-M17. Origins R1a origins The split of R1a (M420) is computed to c. 22,000 or 25,000 years ago, which is the time of the last glacial maximum. A 2014 study by Peter A. Underhill et al., using 16,244 individuals from over 126 populations from across Eurasia, concluded that there was "a compelling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup T (Y-DNA)
Haplogroup T-M184, also known as Haplogroup T, is a human Y-chromosome DNA haplogroup. The unique-event polymorphism that defines this clade is the single-nucleotide polymorphism known as ''M184''. Other SNPs – ''M272'', ''PAGES129'', ''L810'', ''L455'', ''L452'', and ''L445'' – are considered to be phylogenetically equivalent to ''M184''. As a primary branch of haplogroup LT (a.k.a. K1), the basal, undivergent haplogroup T* currently has the alternate phylogenetic name of K1b and is a sibling of haplogroup L* (a.k.a. K1a). (Before 2008, haplogroup T and its subclades were known as haplogroup K2. The name K2 has since been reassigned to a primary subclade of haplogroup K.) It has two primary branches: T1 (T-L206) and T2 (T-PH110). T-M184 is unusual in that it is both geographically widespread and relatively rare. T1 (T-L206) – the numerically dominant primary branch of T-M184 – appears to have originated in Western Asia, and possibly spread from there into the East A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup M30 (mtDNA)
In human mitochondrial genetics, Haplogroup M30 is a human mitochondrial DNA (mtDNA) haplogroup. Origin Haplogroup M30 (coding region: 195A-514dCA-12007-15431) is a South-Asian or an India-specific maternal lineage of the macrohaplogroup M identified by the mutations T195A, G15431A and G12007A. Haplogroup M30 used to be a part of M4 haplogroup distinguished by G15431A. Haplogroup M30 shares a common coding region mutation (12007) together with the M4, M18, M37 and M38 haplogroups from the root of haplogroup M (superhaplogroup M4'30). M4′30 super-clade is the only clade that shares an intermediate lineage between 2 haplogroups, while the rest of all M lineages have originated independently from the root of macrohaplogroup M; thus supporting the idea of rapid dispersal of modern humans along the Asian coast after they left Africa, followed by a long period of isolation. Haplogroup M30 was identified in 2005 based on complete mitochondrial genome sequences of 24 Indian samples. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Y-DNA Haplogroups In Populations Of South Asia
Y-DNA haplogroups in populations of South Asia are haplogroups of the male Y-chromosome found in South Asian populations. Major Y-chromosome DNA haplogroups in South Asia South Asia, located on the crossroads of Western Eurasia and Eastern Eurasia, accounts for about 39.49% of Asia's population, Overview. ''Encyclopædia Britannica''. Encyclopædia Britannica Online, 2009: "The Indian subcontinent is home to a vast diversity of peoples, most of whom speak languages from the Indo-Aryan subgroup of the Indo-European family." The presence of Himalayas in northern and eastern borders of South Asia have limited migrations from Eastern Eurasia into Indian subcontinent in the past. Hence most of the male-mediated migrations into South Asia occurred from Western Eurasia into the region, as seen in the Y-chromosome DNA Haplogroup variations of populations in the region. The major paternal lineages of South Asian populations, represented by Y chromosomes, are haplogroups R1a1, R2, H, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Y-DNA Haplogroups By Ethnic Group
The various ethnolinguistic groups found in the Caucasus, Central Asia, Europe, the Middle East, North Africa and/or South Asia demonstrate differing rates of particular Y-DNA haplogroups. In the table below, the first two columns identify ethnolinguistic groups. Subsequent columns represent the sample size (''n'') of the study or studies cited, and the percentage of each haplogroup found in that particular sample. (Data from studies conducted before 2004 may be inaccurate or a broad estimate, due to obsolete haplogroup naming systems – e.g. the former ''Haplogroup 2'' included members of the relatively unrelated haplogroups known later as Haplogroup G and macrohaplogroup IJ hich comprises haplogroups I and J) See also * Genetics ** Human mitochondrial DNA haplogroups ** Human genome ** Genetic genealogy ** Genealogical DNA testing ** Race and genetics * Genetic history * Timeline of human evolution ** Recent African origin of modern humans ** Genetic history of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Asian Ethnic Groups
South Asian ethnic groups are an ethnolinguistic grouping of the diverse populations of South Asia, including the nations of India, Pakistan, Bangladesh, Nepal, Bhutan, the Maldives, and Sri Lanka. While Afghanistan is variously considered to be part of both Central Asia and South Asia, Afghans are generally not included among South Asians. The majority of the population fall within three large linguistic groups: Indo-Aryan, Dravidian, and Iranic. The Indian, Nepalese, and Sri Lankan societies are traditionally divided into castes or clans, which are based primarily on labour divisions; these categories have had no official status in India since independence in 1947, except for the scheduled castes and tribes, which remain registered for the purpose of affirmative action. In today's India, the population is categorised in terms of the 1,652 mother tongues spoken. These groups are also further subdivided into numerous sub-groups, castes and tribes. Indo-Aryans form the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Studies On Sinhalese
Genetic studies on the Sinhalese is part of population genetics investigating the origins of the Sinhalese population. All studies agree that there is a significant relationship between the Sinhalese and the Bengalis and South Indian Tamils, and that there is a significant genetic relationship between Sri Lankan Tamils and Sinhalese. This is also supported by a genetic distance study, which showed low differences in genetic distance between the Sinhalese and the Bengali, Tamil, and Keralite volunteers. Relationship to Bengalis An Alu polymorphism analysis by Mastana S (2007) using Sinhalese, Tamil, Bengali, Gujarati (Patel), and Punjabi as parental populations found the following proportions of genetic contribution: Analysis of X chromosome STRs by Perera et al. (2021) found the Sinhalese (as well as Sri Lankan Tamils and Sri Lankan Muslims) to be more closely related to Bengalis, than to the Indian Tamils of Sri Lanka.Perera, N., Galhena, G. and Ranawaka, G., 2021. X-ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
R-matrix
The term R-matrix has several meanings, depending on the field of study. The term R-matrix is used in connection with the Yang–Baxter equation. This is an equation which was first introduced in the field of statistical mechanics, taking its name from independent work of C. N. Yang and R. J. Baxter. The classical R-matrix arises in the definition of the classical Yang–Baxter equation. In quasitriangular Hopf algebra, the R-matrix is a solution of the Yang–Baxter equation. The numerical modeling of diffraction gratings in optical science can be performed using the R-matrix propagation algorithm. R-matrix method in quantum mechanics There is a method in computational quantum mechanics for studying scattering known as the R-matrix. This method was originally formulated for studying resonances in nuclear scattering by Wigner and Eisenbud. Using that work as a basis, an R-matrix method was developed for electron, positron and photon scattering by atoms. This approac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eigenvector Analysis
Principal component analysis (PCA) is a popular technique for analyzing large datasets containing a high number of dimensions/features per observation, increasing the interpretability of data while preserving the maximum amount of information, and enabling the visualization of multidimensional data. Formally, PCA is a statistical technique for reducing the dimensionality of a dataset. This is accomplished by linearly transforming the data into a new coordinate system where (most of) the variation in the data can be described with fewer dimensions than the initial data. Many studies use the first two principal components in order to plot the data in two dimensions and to visually identify clusters of closely related data points. Principal component analysis has applications in many fields such as population genetics, microbiome studies, and atmospheric science. The principal components of a collection of points in a real coordinate space are a sequence of p unit vectors, where th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Distance
Genetic distance is a measure of the genetic divergence between species or between populations within a species, whether the distance measures time from common ancestor or degree of differentiation. Populations with many similar alleles have small genetic distances. This indicates that they are closely related and have a recent common ancestor. Genetic distance is useful for reconstructing the history of populations, such as the multiple human expansions out of Africa. It is also used for understanding the origin of biodiversity. For example, the genetic distances between different breeds of domesticated animals are often investigated in order to determine which breeds should be protected to maintain genetic diversity. Biological foundation In the genome of an organism, each gene is located at a specific place called the locus for that gene. Allelic variations at these loci cause phenotypic variation within species (e.g. hair colour, eye colour). However, most alleles do not hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
