Biomaterial Database

X-chromosomal STR based genetic polymorphisms and demographic history of Sri Lankan ethnicities and their relationship with global populations. 2021

Nandika Perera, and Gayani Galhena, and Gaya Ranawaka

Genetech Molecular Diagnostics, Colombo 08, Sri Lanka.

A new 16 X-short tandem repeat (STR) multiplex PCR system has recently been developed for Sr Lankans, though its applicability in evolutionary genetics and forensic investigations has not been thoroughly assessed. In this study, 838 unrelated individuals covering all four major ethnic groups (Sinhalese, Sri Lankan Tamils, Indian Tamils and Moors) in Sri Lanka were successfully genotyped using this new multiplex system. The results indicated a high forensic efficiency for the tested loci in all four ethnicities confirming its suitability for forensic applications of Sri Lankans. Allele frequency distribution of Indian Tamils showed subtle but statistically significant differences from those of Sinhalese and Moors, in contrast to frequency distributions previously reported for autosomal STR alleles. This suggest a sex biased demographic history among Sri Lankans requiring a separate X-STR allele frequency database for Indian Tamils. Substantial differences observed in the patterns of LD among the four groups demand the use of a separate haplotype frequency databases for each individual ethnicity. When analysed together with other 14 world populations, all Sri Lankan ethnicities except Indian Tamils clustered closely with populations from Indian Bhil tribe, Bangladesh and Europe reflecting their shared Indo-Aryan ancestry.

UI	MeSH Term	Description	Entries
D011110	Polymorphism, Genetic	The regular and simultaneous occurrence in a single interbreeding population of two or more discontinuous genotypes. The concept includes differences in genotypes ranging in size from a single nucleotide site (POLYMORPHISM, SINGLE NUCLEOTIDE) to large nucleotide sequences visible at a chromosomal level.	Gene Polymorphism,Genetic Polymorphism,Polymorphism (Genetics),Genetic Polymorphisms,Gene Polymorphisms,Polymorphism, Gene,Polymorphisms (Genetics),Polymorphisms, Gene,Polymorphisms, Genetic
D003710	Demography	Statistical interpretation and description of a population with reference to distribution, composition, or structure.	Demographer,Demographic,Demographic and Health Survey,Population Distribution,Accounting, Demographic,Analyses, Demographic,Analyses, Multiregional,Analysis, Period,Brass Technic,Brass Technique,Demographers,Demographic Accounting,Demographic Analysis,Demographic Factor,Demographic Factors,Demographic Impact,Demographic Impacts,Demographic Survey,Demographic Surveys,Demographic and Health Surveys,Demographics,Demography, Historical,Demography, Prehistoric,Factor, Demographic,Factors, Demographic,Family Reconstitution,Historical Demography,Impact, Demographic,Impacts, Demographic,Multiregional Analysis,Period Analysis,Population Spatial Distribution,Prehistoric Demography,Reverse Survival Method,Stable Population Method,Survey, Demographic,Surveys, Demographic,Analyses, Period,Analysis, Demographic,Analysis, Multiregional,Demographic Analyses,Demographies, Historical,Demographies, Prehistoric,Distribution, Population,Distribution, Population Spatial,Distributions, Population,Distributions, Population Spatial,Family Reconstitutions,Historical Demographies,Method, Reverse Survival,Method, Stable Population,Methods, Reverse Survival,Methods, Stable Population,Multiregional Analyses,Period Analyses,Population Distributions,Population Methods, Stable,Population Spatial Distributions,Prehistoric Demographies,Reconstitution, Family,Reconstitutions, Family,Reverse Survival Methods,Spatial Distribution, Population,Spatial Distributions, Population,Stable Population Methods,Technic, Brass,Technique, Brass
D005006	Ethnicity	A group of people with a common cultural heritage that sets them apart from others in a variety of social relationships.	Ethnic Groups,Nationality,Ethnic Group,Nationalities
D005787	Gene Frequency	The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.	Allele Frequency,Genetic Equilibrium,Equilibrium, Genetic,Allele Frequencies,Frequencies, Allele,Frequencies, Gene,Frequency, Allele,Frequency, Gene,Gene Frequencies
D006239	Haplotypes	The genetic constitution of individuals with respect to one member of a pair of allelic genes, or sets of genes that are closely linked and tend to be inherited together such as those of the MAJOR HISTOCOMPATIBILITY COMPLEX.	Haplotype
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013188	Sri Lanka	Country in southern Asia, an island in the Indian Ocean, south of India. The capital is Colombo.	Ceylon
D015810	Linkage Disequilibrium	Nonrandom association of linked genes. This is the tendency of the alleles of two separate but already linked loci to be found together more frequently than would be expected by chance alone.	Disequilibrium, Linkage,Disequilibriums, Linkage,Linkage Disequilibriums
D053803	Forensic Genetics	The application of genetic analyses and MOLECULAR DIAGNOSTIC TECHNIQUES to legal matters and crime analysis.	Forensic Genetic,Genetic, Forensic,Genetics, Forensic
D018895	Microsatellite Repeats	A variety of simple repeat sequences that are distributed throughout the GENOME. They are characterized by a short repeat unit of 2-8 basepairs that is repeated up to 100 times. They are also known as short tandem repeats (STRs).	Microsatellite Markers,Pentanucleotide Repeats,Simple Repetitive Sequence,Tetranucleotide Repeats,Microsatellites,Short Tandem Repeats,Simple Sequence Repeats,Marker, Microsatellite,Markers, Microsatellite,Microsatellite,Microsatellite Marker,Microsatellite Repeat,Pentanucleotide Repeat,Repeat, Microsatellite,Repeat, Pentanucleotide,Repeat, Short Tandem,Repeat, Simple Sequence,Repeat, Tetranucleotide,Repeats, Microsatellite,Repeats, Pentanucleotide,Repeats, Short Tandem,Repeats, Simple Sequence,Repeats, Tetranucleotide,Repetitive Sequence, Simple,Repetitive Sequences, Simple,Sequence Repeat, Simple,Sequence Repeats, Simple,Sequence, Simple Repetitive,Sequences, Simple Repetitive,Short Tandem Repeat,Simple Repetitive Sequences,Simple Sequence Repeat,Tandem Repeat, Short,Tandem Repeats, Short,Tetranucleotide Repeat