On the population genetics of the red cell glyoxalase I (GLO)

Summary The GLO phenotype distribution was studied in the population from the Rostock area (n=233). The gene frequencies of GLO alleles were estimated to be GLO¹=0.4249, GLO²=0.5751. The electrophoretic separation was achieved on horizontal starch gel.     

Erythrocyte glyoxalase I polymorphism in the owl monkey,Aotus

Three erythrocyte glyoxalase I phenotypes were observed in a sample of 235 karyotypically defined New World owl monkeys, Aotus. The selective distribution of glyoxalase I allele (GLO¹, GLO²) is related to the karyotype of each animal. Owl monkeys with a karyotype VI had an equal distribution of GLO¹ and GLO² genes in the population. Aotus with karyotype II, III, IV, or V had, exclusively, the GLO² allele (expressed as the fast electrophoretic phenotype), in contrast with monkeys with karyotype I or VII, which had only the GLO¹ allele (expressed as the slow electrophoretic phenotype).     

Genetic study in Greek Sarakatsans. I. Blood groups and enzyme polymorphisms

A random sample from the endogamic population of Greek Sarakatsans has been studied for eight blood groups, eleven enzymic genetic systems and haemoglobin variants. The allelic frequencies of the polymorphic loci have been compared with those of other samples from the Greek mainland and other European populations. The Sarakatsans tend to resemble their neighbours. The comparison with European populations indicates that the Sarakatsans have gene frequencies similar to other Mediterranean and European populations. However, the monomorphism of the Kell system, the low frequency of the ACP^*B, AK^*1 and GLO^*1 allelas and the high frequency of the ACP^*C, ESD^*1 and GPT^*1 alleles, are some of the distinguishing features of Sarakatsans. Furthermore, the Sarakatsans are not a high risk population for G6PD deficiency and haemoglobinopathies.     

The distribution of esterase D variants in different ethnic groups

Summary Blood samples collected from a number of human populations belonging to various ethnic groups were screened on cellogel for red-cell esterase D (ESD) variants. These data gathered during the present study together with those that have already appeared in the literature indicate that the common variant allele ESD ² occurs most frequently in the Mongoloid populations, least frequently in the Negroid, and with intermediate frequencies in the Caucasoids. An east to west cline was noticed in the northern populations of the Indian subcontinent; ESD ² gene frequencies in these populations were found to range between those among the Mongoloids and the Caucasoids.     

Polymorphism of red cell glyoxalase 1

Summary Glyoxalase polymorphism has been studied in 7296 persons from populations in South Asia, Southeast Asia, Oceania, Iran, and Colombia. The GLO¹ frequencies are very low in most of Oceania, including Australia, somewhat higher in Southeast Asia, and intermediate though variable in India. In Iran the GLO¹ frequency is similar to that in Europe. The value for the single amerindian group in Colombia is nearly 30%.     

GLO polymorphism in two Polish population samples

Summary The red cell GLO phenotypes were determined in two Polish population samples. A total of 1310 people from the region of Lublin (Southeastern Poland, n=797) and Wrocaw (Southwestern Poland, n=513) were investigated. The gene frequencies were calculated for GLO¹ (=0.4427) and GLO² (=0.5573). The evaluation of 372 mother-child pairs showed no deviation from a hereditary hypothesis.     

Aquaculture related invasion of the exotic <Emphasis Type="Italic">Artemia franciscana</Emphasis> and displacement of the autochthonous <Emphasis Type="Italic">Artemia</Emphasis> populations from the hypersaline habitats of India

Autochthonous parthenogentic Artemia populations have been reported from Indian hypersaline habitats since 1950s. Exotic Artemia franciscana was imported and introduced into India as live food for aquaculture since the early eighties. To assess the present status of the Artemia populations and the possibility of invasion by the introduced A. franciscana in Indian Salinas, an extensive study was conducted using conventional and molecular approaches. Morphological and biometric observations, crossbreeding experiments and molecular and phylogenetic analysis using Internally Transcribed Spacer-1 sequence revealed the extensive presence of alien, sexual A. franciscana populations in various hypersaline areas. Individual culture experiments and crossbreeding studies further confirmed the absence of autochthonous parthenogentic Artemia populations. Lack of regional endemism in populations of distant origins was evident, indicating that the invaded populations have naturalized and are in the process of evolution. This forms the first report of invasion by A. franciscana in hypersaline habitats of Indian subcontinent and further studies are required to assess the biological implications of this invasion.     

Gene diversity in Indian populations

Summary The phenotypes of glyoxalase I (GLO) were determined in a random population from Hessen (Germany) by high-voltage agarose gel electrophoresis. The gene frequencies in 1150 unrelated individuals were 0.4391 for GLO¹ and 0.5609 for GLO². Rare phenotypes were not observed. The segregation of phenotypes in 50 families and 32 mother-child combinations supports the assumed autosomal codominant inheritance. The possibility of a simultaneous typing for GLO, esterase D (EsD), and carbonic anhydrase₂ (CA₂) on one gel is discussed.     

Some remarks on the latitudinal distribution of Cladocera on the Indian subcontinent

One hundred and thirty species of Cladocera have been recorded from the Indian subcontinent which extends from 6°N to 37°N latitude and covers an area of 4.5 million km². The equatorial region has few Daphnia species, all belonging to the sub-genus Ctenodaphnia while the more northern parts have more species of Daphni including Daphnia s. str. The limnetic Cladocera lacks the carnivorous Polyphemidae and Leptodoridae at lower latitudes (equatorial). The common limnetic species of the equatorial region are eurytopic and extend throughout the subcontinent.     

Assessment of variation in Aceria cajani using analysis of rDNA ITS regions and scanning electron microscopy: implications for the variability observed in host plant resistance to pigeonpea sterility mosaic disease

Aceria cajani on pigeonpea (Cajanus cajan) is the vector of the agent of pigeonpea sterility mosaic disease (PSMD), a very damaging virus‐like disease in the Indian subcontinent. PCR was used to amplify A. cajani nuclear ribosomal DNA (rDNA) internal transcribed spacers (ITS) and associated rDNA genes. They were assessed for variation in this genome region by nucleotide sequencing and RFLP. A. cajani‐specific rDNA primers are described. Several A. cajani populations were collected from pigeonpea plants from various PSMD endemic locations in India, Nepal and Myanmar. No significant variation was identified in rDNA regions, or in morphological features. These results suggest strongly that A. cajani on pigeonpea across the Indian subcontinent constitutes one species and that no other Aceria species and probably no A. cajani biotypes that differ in vectoring ability are involved in the transmission of the agent of PSMD. The implications of these findings for the variability observed in PSMD‐resistant pigeonpea genotypes across various locations in India are discussed.     

Ancestral modal Y-STR haplotype shared among Romani and South Indian populations

One of the primary unanswered questions regarding the dispersal of Romani populations concerns the geographical region and/or the Indian caste/tribe that gave rise to the proto-Romani group. To shed light on this matter, 161 Y-chromosomes from Roma, residing in two different provinces of Serbia, were analyzed. Our results indicate that the paternal gene pool of both groups is shaped by several strata, the most prominent of which, H1-M52, comprises almost half of each collection's patrilineages. The high frequency of M52 chromosomes in the two Roma populations examined may suggest that they descend from a single founder that has its origins in the Indian subcontinent. Moreover, when the Y-STR profiles of haplogroup H derived individuals in our Roma populations were compared to those typed in the South Indian emigrants from Malaysia and groups from Madras, Karnataka (Lingayat and Vokkaliga castes) and tribal Soligas, sharing of the two most common haplotypes was observed. These similarities suggest that South India may have been one of the contributors to the proto-Romanis. European genetic signatures (i.e., haplogroups E1b1b1a1b-V13, G2a-P15, I-M258, J2-M172 and R1-M173), on the other hand, were also detected in both groups, but at varying frequencies. The divergent European genetic signals in each collection are likely the result of differential gene flow and/or admixture with the European host populations but may also be attributed to dissimilar endogamous practices following the initial founder effect. Our data also support the notion that a number of haplogroups including G2a-P15, J2a3b-M67(xM92), I-M258 and E1b1b1-M35 were incorporated into the proto-Romani paternal lineages as migrants moved from northern India through Southwestern Asia, the Middle East and/or Anatolia into the Balkans.     

Inactivation dates of the human and guinea pig vitamin C genes

The capacity to biosynthesize ascorbic acid has been lost in a number of species including primates, guinea pigs, teleost fishes, bats, and birds. This inability results from mutations in the GLO gene coding for L-gulono-γ-lactone oxidase, the enzyme responsible for catalyzing the last step in the vitamin C biosynthetic pathway. We analyzed available primate and rodent GLO gene sequences to determine their evolutionary history. We used a method based on sequence comparisons of lineages with and without functional GLO genes to calculate inactivation dates of 61 and 14 MYA for the primate and guinea pig genes, respectively. These estimates are consistent with previous phylogeny-based estimates. An analysis of transposable element distribution in the primate and rodent GLO sequences did not reveal conclusive evidence that illegitimate recombination between repeats has contributed to the loss of exons in the primate and guinea pig genes.     

One and the same: integrative taxonomic evidence that Bactrocera invadens (Diptera: Tephritidae) is the same species as the Oriental fruit fly Bactrocera dorsalis

The invasive fruit fly Bactrocera invadens Drew, Tsuruta & White, and the Oriental fruit fly Bactrocera dorsalis (Hendel) are highly destructive horticultural pests of global significance. Bactrocera invadens originates from the Indian subcontinent and has recently invaded all of sub‐Saharan Africa, while B. dorsalis principally occurs from the Indian subcontinent towards southern China and South‐east Asia. High morphological and genetic similarity has cast doubt over whether B. invadens is a distinct species from B. dorsalis. Addressing this issue within an integrative taxonomic framework, we sampled from across the geographic distribution of both taxa and: (i) analysed morphological variation, including those characters considered diagnostic (scutum colour, length of aedeagus, width of postsutural lateral vittae, wing size, and wing shape); (ii) sequenced four loci (ITS1, ITS2, cox1 and nad4) for phylogenetic inference; and (iii) generated a cox1 haplotype network to examine population structure. Molecular analyses included the closely related species, Bactrocera kandiensis Drew & Hancock. Scutum colour varies from red‐brown to fully black for individuals from Africa and the Indian subcontinent. All individuals east of the Indian subcontinent are black except for a few red‐brown individuals from China. The postsutural lateral vittae width of B. invadens is narrower than B. dorsalis from eastern Asia, but the variation is clinal, with subcontinent B. dorsalis populations intermediate in size. Aedeagus length, wing shape and wing size cannot discriminate between the two taxa. Phylogenetic analyses failed to resolve B. invadens from B. dorsalis, but did resolve B. kandiensis. Bactrocera dorsalis and B. invadens shared cox1 haplotypes, yet the haplotype network pattern does not reflect current taxonomy or patterns in thoracic colour. Some individuals of B. dorsalis/B. invadens possessed haplotypes more closely related to B. kandiensis than to conspecifics, suggestive of mitochondrial introgression between these species. The combined evidence fails to support the delimitation of B. dorsalis and B. invadens as separate biological species. Consequently, existing biological data for B. dorsalis may be applied to the invasive population in Africa. Our recommendation, in line with other recent publications, is that B. invadens be synonymized with B. dorsalis.     

Isolation and characterization of polymorphic microsatellites in Labeo rohita and their cross‐species amplification in related species

The major Indian carps namely rohu (Labeo rohita), catla (Catla catla), mrigal (Cirrhinus mrigala) and calbasu (Labeo calbasu) are important freshwater species of the Indian subcontinent constituting over 65% of the fish produce. In the present study, isolation of 12 microsatellite loci from rohu has been reported. Cross‐species amplification in related carps and their implication in population genetic studies as well as selective breeding program were discussed.     

Impact of body melanisation on contrasting levels of desiccation resistance in a circumtropical and a generalist <Emphasis Type="Italic">Drosophila</Emphasis> species

We investigated the role of cuticular lipids, body melanisation and body size in conferring contrasting levels of desiccation resistance in latitudinal populations of Drosophila melanogaster and Drosophila ananassae on the Indian subcontinent. Contrary to the well known role of cuticular lipids in water proofing in diverse insect taxa, there is lack of geographical variations in the amount of cuticular lipids per fly in both the species. In D. ananassae, quite low levels of body melanisation are correlated with lower desiccation resistance. By contrast, increased levels of desiccation resistance are correlated with quite high melanisation in D. melanogaster. Thus, species specific cuticular melanisation patterns are significantly correlated with varying levels of desiccation resistance within as well as between populations and across species. Role of body melanisation in desiccation resistance is further supported by the fact that assorted dark and light flies differ significantly in cuticular water loss, hemolymph and dehydration tolerance. However, similar patterns of body size variation do not account for contrasting levels of desiccation resistance in these two Drosophila species. Climatic selection is evidenced by multiple regression analysis with seasonal amplitude of thermal and humidity changes (Tcv and RHcv) along latitude on the Indian subcontinent. Finally, the contrasting levels of species specific distribution patterns are negatively correlated with RHcv of sites of origin of populations i.e. a steeper negative slope for D. ananassae corresponds with its desiccation sensitivity as compared with D. melanogaster. Thus, evolutionary changes in body melanisation impact desiccation resistance potential as well as distribution patterns of these two Drosophila species on the Indian subcontinent.     

The dagestan gene pool: Analysis of the frequencies of classical genetic markers in Avars

This study is part of long-term research in the gene pool of Dagestan ethnic groups. The phenotype (in percent), gene, and haplotype frequencies in three Avar populations are reported. A total of 37 alleles of 13 loci of immune and biochemical genetic marker systems (ABO, Rhesus, P, Lewis, HP, GC, C′3, TF, 6PGD, GLO1, ESD, ACP, and PGM1) have been studied. Rare haplotypes of the Rhesus system (CDE, Cde and cdE) have been found in the populations studied. In two out of three local populations (Khunzakh and Kharakhi), a typically “Caucasoid” rare gene ACP1 ^c of the AcP1 locus has proved to be relatively frequent (0.030 and 0.023, respectively). The frequencies of the allele variantsP ² , le, and Hp ¹ of loci of the P, Lewis, and HP systems, respectively, have been found to be lower than in other Caucasian ethnic groups and the total northern Eurasian population. The mean allele frequencies for the GC, C′3, TF, 6PGD, GLO1, and ESD systems in the populations studied are comparable wit those for both Caucasian ethnic groups and the total population of the European historical ethnographic province. Statistical analysis of the results has shown 11 cases of significant deviations of the observed phenotype frequencies from the Hardy-Weinberg equilibrium.     

Red cell glutathione peroxidase (GPX1) variation in Afro-Jamaican,Asiatic Indian,and Dutch populations

Summary A Cellogel procedure for screening the electrophoretic variants of the human red cell glutathione peroxidase (GPX1) was described. Three hundred and ninety eight Dutch persons living in various parts of The Netherlands, 385 individuals born in various states of India, and 72 Jamaicans of African origin livig in Birmingham, UK, were screened for GPX1 variants. The Dutch were monomorphic, while one Afro-Jamaican female and two males and one female of the 116 Punjabis were found to be variants indistinguishable from each other in their pattern of electrophoresis. The clear five banded pattern of the variant indicated that the subunit structure of the human red cell glutathione peroxidase is most probably a tetramer and suggested that the variant is the expression of a heterozygote due to alleles at an autosomal locus. The corresponding phenotype was designated tentatively as GPX1 2-1 and the alleles as GPX1 ^*1 and GPX1 ^*2 respectively. The variant 2-1 was found to be identical to the Thomas variant described by Beutler and West (1974). Thus so far, in addition to the Afro-Americans and Ashkenazi Jews (Beutler et al. 1974), the Punjabis of the Indian subcontinent (this report) were found to exhibit the GPX1 polymorphism due to the GPX1 ^*2 allele. The data discussed in this paper (which included unpublished observations on several African and non-African populations) suggest that the GPX1 ^*2 allele is originally an African variant and hint that the present day Punjabis of Indian subcontinent, like Ashkenazi Jews, are predominantly of Mediterranean origin with some proportion of African ancestry (Mourant et al. 1976).     

Origin and radiation of the house mouse: mitochondrial DNA phylogeny

On the basis of patterns of allele frequency variation in nuclear genes (Din et al., in press) it has been proposed that the house mouse M. musculus originated in the northern Indian subcontinent, from where it radiated in several directions to form the well-described peripheral subspecies (M. m. domesticus, M. m. musculus and M. m. castaneus). Here we use a mitochondrial DNA (mtDNA) phylogeny to test this hypothesis and to analyse the historical and demographic events that have accompanied this differentiation. This marker also provides a powerful means to check for genetic continuity between the central and peripheral populations. We studied restriction site polymorphism of samples from India and the Middle East as well as samples from the rest of Eurasia and northern Africa. M. m. domesticus and M. m. musculus are both monophyletic for mtDNA and belong to the subspecies-specific mtDNA lineages that have been described previously. Average nucleotide diversity is low in M. m. musculus (0.2–5%). It is not only higher in M. m. domesticus (0.7–0.9%) but the distribution of pairwise divergence is wider, and the rate of evolution in this branch appears to be higher than in M. m. musculus. The nucleotide diversity found in M. m. castaneus (0.4%) is due to the existence of two rather divergent linages with little intralineage variation. These two lineages are part of a diversified bush of the phylogenetic tree that also comprises several previously undescribed branches and includes all samples from the northern Indian subcontinent and Iran. The degree of diversity found in each of the samples from this region is high (1.2–2.4%) although they come from small geographic areas. This agrees well with the idea that the origin of the radiation was in the northern Indian subcontinent. However, as neither haplotypes on the M. m. domesticus nor on the M. m. musculus branches were found in this region, there appear to be important phylogeographic discontinuities between this central region and these peripherial subspecies. On the basis of the present result and the nuclear data (Din et al., in press), we propose that M. musculus originated in the north of the indian subcontinent. Our calibration of the evolutionary rate of mtDNA in mice suggests that the mouse settlement in this region could be as old as 900 000 years. Possibly from there, a first radiation could have reach the Middle East and the Caspian Sea, where the M. m. domesticus and M. m. musculus lineages, respectively, would have started to differentiate a few hundred thousand years ago, and from where they could have colonised the peripheral part of their ranges only recently.M. m. castaneus appears from its mtDNA to be recent offshoot of the northern Indian population. This multiple and gradual radiation ultimately led to recent peripheral secondary contacts, such as the well-known European hybrid zone.     

Genetic differentiation of Albizia lebbeck (L.) Benth. populations estimated by RAPD and ISSR markers

Abstract

Albizia lebbeck (L.) Benth., a popular multi‐purpose legume tree species, has a wide distribution throughout the Indian subcontinent. The species is highly valued for its quality timber, gum yield and therapeutical uses. However, the increasing social and economical pressures are devastating the natural stands of A. lebbeck forests. So, there is a need to estimate the genetic variation present in A. lebbeck populations. Both RAPD and ISSR molecular markers were used to analyse 172 individuals representing eight populations of the species in different geographical range. The within‐population genetic diversity ranged from 1.23 to 1.38. The total gene variability was 0.34 of which 0.17 (50%) accounted for within‐population gene variability. The genetic differentiation between populations (Gst = 0.49) was significantly correlated to geographical distance (r = 0.61, p < 0.001). An UPGMA clustering suggests a high level of genetic isolation due to distance. This study revealed the genetic differentiation which will provide a template for adaptation and evolution of the populations and species.