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Rineloricaria is the most diverse genus within the freshwater fish subfamily Loricariinae, and it is widely distributed in the Neotropical region. Despite limited cytogenetic data, records from southern and south‐eastern Brazil suggest a high rate of chromosomal rearrangements in this genus, mirrored in remarkable inter‐ and intraspecific karyotype variability. In the present work, we investigated the karyotype features of Rineloricaria teffeana, an endemic representative from northern Brazil, using both conventional and molecular cytogenetic techniques. We revealed different diploid chromosome numbers (2n) between sexes (33♂/34♀), which suggests the presence of an ♀X1X1X2X2/♂X1X2Y multiple sex chromosome system. The male‐limited Y chromosome was the largest and the only biarmed element in the karyotype, implying Y‐autosome fusion as the most probable mechanism behind its origination. C‐banding revealed low amounts of constitutive heterochromatin, mostly confined to the (peri)centromeric regions of most chromosomes (including the X2 and the Y) but also occupying the distal regions of a few chromosomal pairs. The chromosomal localization of the 18S ribosomal DNA (rDNA) clusters revealed a single site on chromosome pair 4, which was adjacent to the 5S rDNA cluster. Additional 5S rDNA loci were present on the autosome pair 8, X1 chromosome, and in the presumed fusion point on the Y chromosome. The probe for telomeric repeat motif (TTAGGG)n revealed signals of variable intensities at the ends of all chromosomes except for the Y chromosome, where no detectable signals were evidenced. Male‐to‐female comparative genomic hybridization revealed no sex‐specific or sex‐biased repetitive DNA accumulations, suggesting a presumably low level of neo‐Y chromosome differentiation. We provide evidence that rDNA sites might have played a role in the formation of this putative multiple sex chromosome system and that chromosome fusions originate through different mechanisms among different Rineloricaria species. [ABSTRACT FROM AUTHOR]

The Brazilian population is a product of asymmetric admixture among European men and Amerindian and African women. However, Brazilian subcontinental ancestry is scarcely documented, especially regarding its African roots. Here, we aimed to unveil the uniparental continental and subcontinental contributions from distinct Brazilian regions, including South (n = 43), Southeast (n = 71), the poorly genetically characterized Central-Western region (n = 323), and a subset of unique Brazilian Amerindians (n = 24), in the context of their genome-wide ancestral contributions. The overwhelming majority of European Y haplogroups (85%) contrast sharply with the predominant African and Amerindian mtDNA haplogroups (73.2%) in admixed populations, whereas in Amerindians, non-Native haplogroups could only be detected through the paternal line. Our in-depth investigation of uniparental markers showed signals of an Andean and Central-Brazilian Amerindian maternal contribution to Southeastern and Central-Western Brazil (83.1 ± 2.1% and 56.9 ± 0.2%, respectively), the last having the highest paternal Amerindian ancestry yet described for an admixed Brazilian region (9.7%) and contrasting with higher Southern-Brazilian Amerindian contribution to Southern Brazil (59.6 ± 1%). Unlike the higher African Bantu contribution previously reported for the South and Southeast, a relevant Western African non-Bantu contribution was detected in those regions (85.7 ± 5% and 71.8 ± 10.8% respectively). In contrast, a higher Bantu contribution was described for the first time in the Central-West (64.8 ± 1.3% maternal and 86.9 ± 9.6% paternal). We observed sex-biased signatures consistent with the historically recorded Brazilian colonization and added new insights in the subcontinental maternal ancestry of Brazilians from regions never studied at this level. [ABSTRACT FROM AUTHOR]

In many animal species, sex determination is accomplished by heterogamety i.e., one of the sexes produces two types of gametes, which upon fertilization will direct the development toward males or females. Both male ("XY") and female ("ZW") heterogamety are known to occur and can be easily distinguished when the sex-chromosomes are morphologically different. However, this approach fails in cases of homomorphic sex chromosomes, such as the sand fly Lutzomyia longipalpis s.l. (Psychodidae, Diptera), which is the main vector of visceral leishmaniosis in Brazil. In order to identify the heterogametic sex in L. longipalpis s.l., we did a whole-genome sequencing of males and females separately and used the "Y chromosome Genome Scan" (YGS) method to find sex-specific sequences. Our results, which were confirmed by PCR, show that L. longipalpis s.l. has XY system. The YGS method can be especially useful in situations in which no morphological difference is observed in the sex-chromosomes or when fresh specimens are not readily available. [ABSTRACT FROM AUTHOR]

The non-recombining nature of the Y chromosome and the well-established phylogeny of Y-specific Single Nucleotide Polymorphisms (Y-SNPs) make them useful for defining haplogroups with high geographical specificity; therefore, they are more apt than the Y-STRs to detect population stratification in admixed populations from diverse continental origins. Different Y-SNP typing strategies have been described to address issues of population history and movements within geographic territories of interest. In this study, we investigated a set of 41 Y-SNPs in 1217 unrelated males from the five Brazilian geopolitical regions, aiming to disclose the genetic structure of male lineages in the country. A population comparison based on pairwise FST genetic distances did not reveal statistically significant differences in haplogroup frequency distributions among populations from the different regions. The genetic differences observed among regions were, however, consistent with the colonization history of the country. The sample from the Northern region presented the highest Native American ancestry (8.4%), whereas the more pronounced African contribution could be observed in the Northeastern population (15.1%). The Central-Western and Southern samples showed the higher European contributions (95.7% and 93.6%, respectively). The Southeastern region presented significant European (86.1%) and African (12.0%) contributions. The subtyping of the most frequent European lineage in Brazil (R1b1a-M269) allowed differences in the genetic European background of the five Brazilian regions to be investigated for the first time. [ABSTRACT FROM AUTHOR]

In this work, the YfilerPlus kit was used to investigate a sample of 258 males from Rio de Janeiro. In addition, the previous database of 760 Yfiler profiles deposited in the YHRD was updated to 1610. YfilerPlus markers showed a high haplotype diversity (0.99997), with only one haplotype shared by two individuals. When only considering the Yfiler markers, the haplotype diversity was slightly lower (0.99976), with 5 haplotypes shared by two individuals and 1 haplotype shared by three individuals. Low genetic distances were found between the Rio de Janeiro and European populations as well as the European/Hispanic American samples. [ABSTRACT FROM AUTHOR]

In a large variety of genetic studies, probabilistic inferences are made based on information available in population databases. The accuracy of the estimates based on population samples are highly dependent on the number of chromosomes being analyzed as well as the correct representation of the reference population. For frequency calculations the size of a database is especially critical for haploid markers, and for countries with complex admixture histories it is important to assess possible substructure effects that can influence the coverage of the database. Aiming to establish a representative Brazilian population database for haplotypes based on 23 Y chromosome STRs, more than 2,500 Y chromosomes belonging to Brazilian, European and African populations were analyzed. No matter the differences in the colonization history of the five geopolitical regions that currently exist in Brazil, for the Y chromosome haplotypes of the 23 studied Y-STRs, a lack of genetic heterogeneity was found, together with a predominance of European male lineages in all regions of the country. Therefore, if we do not consider the diverse Native American or Afro-descendent isolates, which are spread through the country, a single Y chromosome haplotype frequency database will adequately represent the urban populations in Brazil. In comparison to the most commonly studied group of 17 Y-STRs, the 23 markers included in this work allowed a high discrimination capacity between haplotypes from non-related individuals within a population and also increased the capacity to discriminate between paternal relatives. Nevertheless, the expected haplotype mutation rate is still not enough to distinguish the Y chromosome profiles of paternally related individuals. Indeed, even for rapidly mutating YSTRs, a very large number of markers will be necessary to differentiate male lineages from paternal relatives. [ABSTRACT FROM AUTHOR]

Abstract: Fourteen Y-STR loci (DYS458, DYS439, Y-GATA H4, DYS576, DYS447, DYS460, DYS456, YGATA A10, DYS437, DYS449, DYS570, DYS635 or Y-GATA C4, DYS448 and DYS438) were analysed in 873 males from eight northern Brazil populations: Belém (N =400), Santarém (N =69), Manaus (N =75), Macapá (N =65), Palmas (N =30), Rio Branco (N =32), Porto Velho (N =135) and Boa Vista (N =67). A total of 871 different haplotypes were identified, of which 869 were unique. The panel''s estimated total haplotype diversity (HD) is 0.9988, and its discrimination capacity (DC) is 0.9980. The lowest estimates of genetic diversity correspond to markers Y-GATA H4 (0.550) and DYS460 (0.581), and the greatest (above 0.700) to markers DYS458, DYS576, DYS447, YS449, DYS570 and DYS635. The genetic parameters obtained were higher for the 14-Y-STR panel than that for the minimum haplotype set (HD=0.9969; DC=0.76) and the parameters were similar to those obtained with the panel of 17 YSTR of YHRD (HD=0.9987; DC=0. 9870). The analysis of molecular variance (AMOVA) indicated that most of the genetic variance is found within populations and a smaller, but significant part, is found among populations (R ST =0.027, p value=0.009). The data when compared with those from African, Amerindian and European populations have shown no significant genetic distance between northern Brazil populations and Europeans, but there is a significant genetic distance when compared to Africans and Amerindians. The discrimination capacity of the markers shows a high potential for forensic analysis. [Copyright &y& Elsevier]

Y chromosome markers have been widely studied due to their various applications in the fields of forensic and evolutionary genetics. In this study, 35 Y-SNPs and 17 Y-STRs were genotyped in 253 males from the State of Espirito Santo, Brazil. A total of 18 haplogroups and 243 haplotypes were detected; the haplogroup and haplotype diversities were 0.7794 and 0.9997, respectively. Genetic distance analysis using the Y-STR data showed no statistically significant differences between Espirito Santo and other admixed populations from Brazil. The classification of paternal lineages based on haplogroups showed a predominant European contribution (85.88 %), followed by African (11.37 %) and Amerindian (2.75 %) contributions. [ABSTRACT FROM AUTHOR]

The article examines the results of Y-STR genetic marker analysis in Brazilian and South Amerindian populations in Rio Grande do Sul. No genetic substructuring was observed in the comparisons performed with those already published. Multidimensional scaling confirmed the proposed European source of most Y-chromosome Brazilian patrilineages.

Abstract  A male sample of 135 African descendents from the Rio de Janeiro population were typed for the 12 Y-chromosome short tandem repeat (STR) loci included in the PowerPlex Y System. A high haplotype diversity was observed (0.9971), with 91% of haplotypes being unique, demonstrating the usefulness and informative power of this Y-STR set in male lineage identification. Samples with shared haplotypes were additionally typed with the Yfiler kit, which includes five extra markers. The haplotype diversity when using the 17-Yfiler loci increased to (0.9998) with 97% unique haplotypes. The same set of Y-STRs was also typed in 135 father/son pairs and three single-step mutations were observed: one at DYS19 and two at DYS385. Genetic distance analysis showed highly significant differences in all pairwise comparisons between this sample of African descendents and the general population from Rio de Janeiro, as well as with Iberian and African samples from Portugal, Mozambique, Angola and Equatorial Guinea. Comparisons with samples from other regions in Brazil showed that heterogeneity does exist, indicating that a Y-haplotype database for the whole country should take into account the population sub-structure. Moreover, a strong European influence was detected, and thus, a Y-chromosome STR profile proves a rather poor indicator for the ethnic origin of an individual in Rio de Janeiro. [ABSTRACT FROM AUTHOR]

Twenty-one specimens of Aotus were captured on both sides of the Tocantins river when the hydroelectric reservoir of Tucurui, Brazil, was filled. The males had a diploid number of 49 chromosomes, and the females had 50. The observed difference is a consequence of the fusion of the Y chromosome with an autosome. The karyotype is similar to that of the Bolivian Aotus (A. azarae boliviensis). It differs, however, in the G- and C-banding patterns of the chromosome resulting from the Y/autosome fusion. The nucleolar organizing region is located on the secondary constriction of a pair of submetacentric chromosomes. Considerations are presented on the classification of A. infulatus as a separate species. [ABSTRACT FROM AUTHOR]

In this study, the genetic variations of 23 short tandem repeats on the Y-chromosome were analyzed in a sample of 201 males from the Federal District (Brazil). The Federal District (Brazil) was built in 1960 in Brazil's Central West region, where there was no previous population. In 2010, the population of this artificially founded district consisted of 2,500,000 inhabitants. We observed 200 different haplotypes, 199 of which were unique and one of which occurred two times. The haplotype diversity was 0.9999, and the discrimination capacity was 0.995. The data are available in the Y chromosome haplotype reference database under accession number YA003843. The results were compared to the haplotypes from other Brazilian macroregions. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, a Brazilian population, located in the Rondônia state, was genetically characterized for a set of Y chromosome specific STRs included in the Applied Biosystems kit (AmpFℓSTR®Yfiler™), which allows the simultaneous amplification of 16 markers: DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385a/b, DYS438, DYS439, DYS437, DYS448, DYS456, DYS458, DYS635 and GATA H4. The studied population from Rondônia state, in the North of Brazil, included individuals with admixed Native American, African and European ancestry. When comparing Rondônia with other Brazilian populations no significant genetic distances were found. In the comparison with other worldwide populations, although a predominant male European influence could be detected, there were significant differences with some populations from Central and South America and Africa. [Copyright &y& Elsevier]

POPULATION: Unrelated males from the São Paulo State, Brazil ( n=617). [ABSTRACT FROM AUTHOR]

• High Y-STR haplotype diversities were found in Brazilian populations. • Pairwise genetic distances indicate a homogeneity among admixed Brazilian populations. • Brazilian admixed populations showed high proportions of European male lineages. • Y-STR haplogroup prediction tools showed error rates up to 5% in admixed populations. The use of Y-chromosomal genetic markers in forensic investigations demands the establishment of reliable and representative DNA databases of different reference populations. The genetic characterization of the Y chromosome variation in human populations requires the analyses of haplotype frequencies allied to haplogroup determination. The present study aimed to contribute to the Brazilian database by providing 1,382 Yfiler Plus individual profiles, from 11 Brazilian states. The Yfiler Plus markers showed high haplotype diversities in all Brazilian populations (>0.9970), allowing high intra-population discrimination in forensic investigations. Pairwise genetic distances showed a homogeneity between Brazilian populations (F ST ≤ 0.0043; non-differentiation p-values ≥ 0.0212), indicating that admixed populations from Brazil can be represented in a single Yfiler Plus haplotype database, for forensic purposes. The performance of Haplogroup Predictor and NevGen software in haplogroup prediction based on Yfiler Plus and Yfiler haplotypes was evaluated in a subset of 416 Brazilian samples that were also genotyped for 51 Y-SNPs. In 25% of the samples, no classification or errors were found for at least one of the prediction tools or marker sets. NevGen presented lower error rates (5.52% and 8.65% with Yfiler Plus and Yfiler, respectively) than Haplogroup Predictor (16.11% with Yfiler Plus and 13.70% with Yfiler). In conclusion, both haplogroup prediction tools can be useful to direct the SNP typing, but present large error rates to be used in forensic analysis, especially in predicting African haplogroups in admixed South American populations. [ABSTRACT FROM AUTHOR]

Abstract: Brazilian Centro-Oeste region settlement was derived from national internal migrations of already mixed individuals. A Brazilian peculiarity, which occurred during the population formation, was the directional mating between European males and Amerindian or African females. Seeking the improvement of the knowledge about Goiás and Federal District population history, we studied the distribution of Y-haplogroups in samples of these populations. According to the data obtained, Federal District genetic diversity rate was greater than Goiás, which reflected a small divergence between these two neighbors'' populations but statistically unsupported (P =0.0524). The European contribution was similar in both population and greater than African and Amerindian ones. In Federal District, a little contribution from Japan was also observed. [Copyright &y& Elsevier]

Y-chromosomal STRs are important markers in forensic genetics, due to some peculiar characteristics. The absence of recombination makes them a useful tool to infer kinship in complex cases involving distant paternal relatives, or to infer paternal bio-geographic ancestry. The presence of a single copy, being transmitted from father to son, allow tracing mutational events in Y-STRs without ambiguity. For the statistical interpretation of forensic evidences based on Y-STR profiles, it is necessary to have estimates on both mutation rates and haplotype frequencies. In this work, 407 father-son duos from São Paulo and Rio de Janeiro states and 204 unrelated individuals from Manaus were analyzed. Haplotype frequencies and mutation rates for the Y-STRs from the PowerPlex Y23 commercial kit were estimated. Thirty-six mutations were observed in 15 of the 22 Y-STRs analyzed, for an average mutation rate of 3.84 × 10 -3 (95 % CI 2.69 × 10 -3 to 5.32 × 10 -3 ). All mutations in GAAA repeats occurred in alleles with 13 or more uninterrupted units. Mutations in GATA repeats were observed in alleles with 9-17 uninterrupted units. An analysis carried out in different father's age groups showed an increase of 2.48 times the mutation rate in the age group of 40-50 years, when compared to the 20-30 age group, in agreement with the described for autosomal STRs. A high haplotype diversity was found in the three Brazilian populations. Pairwise genetic distance analysis (F ST ) showed no significant differences between the three populations in this study, which were also close to populations with strong European influence. The highest distances among the Brazilian populations were with São Gabriel da Cachoeira, which has a high Native American ancestry., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Abstract: Alagoas State is located in Northeast Brazil. Like many other South American populations, the genetic composition of Alagoas is the result of admixture between Amerindians, Europeans and Africans. In this work, 24 Y chromosome SNPs were analysed (SRY10831, M168, M213, M9, M22, M45, M3, M173, M17, P25, M269, M70, M201, M170, M26, M304, M172, M96, M2, M35, M78, M81, M123 and M34) in a sample of 247 unrelated men belonging to Alagoas population, aiming to determine the different Amerindian, European and African male contributions to the current population. SNP typing was done by a single base extension method, using the SNaPshot minisequencing kit. A total of 16 haplogroups were found in our sample. The main contribution to the present day Y chromosome genepool of Alagoas was found to be European (94.74%), and a much lower percentage of African (4.45%) and Amerindian (0.81%) ancestry lineages have been detected. When our sample was compared with others from Portugal and Rio de Janeiro, no significant genetic differences could be observed. [Copyright &y& Elsevier]

Abstract: Genetic differentiation can exist not only between populations but also between different groups within a population, which must have to be taken into account in forensic databasing. The analysis of Y chromosome SNPs has shown to be a powerful tool to detect population substructure, critical in admixed populations as it is the case of Brazilian as well as most American populations. With this work, we aimed to study the origin of paternal lineages (Y-SNPs) in a sample of Sub-Saharan Africa descendents living in Rio de Janeiro. A low proportion of YAP+ chromosomes were found (≈42%), a mutation usually represented in almost 80% of the male lineages in Bantu populations. Concerning the YAP− chromosomes, all of them carried the M89 mutation, and the most common lineages were those belonging to the European R1b1-P25 haplogroup, with a frequency of 37.12%. As expected, a much higher proportion of YAP+ chromosomes were found in this sample than in Rio de Janeiro general population (19%). Nevertheless, in accordance with other studies on African ancestry groups in America, our results revealed a high proportion of European Y lineages in Afro-Brazilians from Rio de Janeiro. [Copyright &y& Elsevier]

Abstract: In recent years, an interest has grown with Y-chromosome single nucleotide polymorphisms (Y-SNPs) and their potential applications, especially in evolutionary biology, forensics and medical genetics. A total of 81 samples from unrelated males of the Brazilian population of São Paulo State (Ribeirão Preto) have been analyzed for 14 Y-SNPs (SRY1532, M213, M9, M70, M22, TAT, 92R7, M173, P25—multiplex 1; M170, M62, M172, M26 and M201—multiplex 2) using the SNaPshot™ methodology, and haplogroups frequencies were determined. European influence (mainly due to the male Portuguese settlers, but also the later arrival of Spanish and Italian) is therefore confirmed, given the fact that the most predominant European haplogroup R1b1 is also the most representative haplogroup (53.09%), followed by haplogroup J2 (with not more than 12.35%). The remaining haplogroups have made a minor contribution, between 9.88% and 1.23%, yet very significant. [Copyright &y& Elsevier]

Abstract: The non-recombining portion of the human Y (NRY) chromosome has various types of variation, including single nucleotide polymorphism (SNP) variation. The study of this specific region can be helpful in forensics, since Y haplogroups show regional specificity, providing useful information about geographic origin of an individual or evidence under investigation. In this study, single nucleotide polymorphisms (SNPs) located on the Y chromosome specific region (M96, M2, M35, M78, M81, M123, M34, M201, M170, M304, M26 and M172) were used to characterize a population sample of 100 males from Bahia, in order to investigate the frequency distribution of the male lineages. These SNPs were selected from the set of 24 SNPs that determine the 11 frequent haplogroups present in Brazilian population. Genotyping was made using SNaPshot kit (Applied Biosystems) in two multiplexes: one with five Y-SNPs (M304, M201, M170, M26 and M172) and another with seven Y-SNPs (M34, M35, M2, M78, M96, M123 and M81). The results validation was done using the software GeneMapper v3.2 (Applied Biosystems). The Y chromosomes not characterized by the SNP set tested (48.0%) were assigned ABCDF(xG,I,J) and will be analyzed with additional markers set. The most frequent haplogroup identified was E1b1a*-M2 (19.0%), followed by J2*-M172 (7.0%), E1b1b1a*-M78 (5.00%), G*-M201 (5.00%), I*(xI2a2)-M170 (4.0%), J*(XJ2)-M304 (4.00%), E1b1b1c1-M34 (3.0%), I2a2*-M26 (3.00%), E*(xE1b1a-b)-M96 (1.0%) and E1b1b1b*-M81 (1.0%). The DNA fragments amplified by PCR showed that the extracted DNA had good amplification. [Copyright &y& Elsevier]

Abstract: This work relates the identification of the 13 carbonized corpses in a car crash in which DNA analysis was necessary. The corpses and relatives samples were tested using polymerase chain reaction (PCR) amplification and short tandem repeat (STR and Y-STR) typing. Amplification products were analyzed by an automated sequencer and statistical analyses were performed using Familias 1.7 software. Full profiles were obtained for all samples. All victim samples had relationship to the reference samples, with agreement for all autosomal markers and the Y chromosome haplotype. Human identification through DNA analysis is an extremely efficient tool in forensic casework when other methods are not successful, even in cases of carbonized bodies. [Copyright &y& Elsevier]

Abstract: Two women were found dead inside a residence. Choke causes death in one that had been naked in a bed and contusion injury in another that was found on a sofa. Were received samples of vaginal and anal swabs of the two victims of homicide with suspected of having suffered sexual violence. References also received samples of two victims and a suspect. We performed genetic analysis for identification of samples from the meeting of any possibility of overlap between patterns and profiles of sequences of deoxyribonucleic acid (DNA) based on genetic relationship between those involved. The reference samples were subjected to the procedure of extraction of nuclear DNA by Chelex method and the swabs samples by differential extraction. For all the samples were performed for amplification of STRs loci and autosomal STRs of chromosome Y. The profiles of DNA sequences were obtained by the Polymerase Chain Reaction (PCR), using sequences starting with marked substances emitting fluorescence detected by reading the optical laser in 3100 Avant automatic sequencer from Applied Biosystems. The information of consecutive loci of Short Repeats or STRs of autosomal chromosomes and the Y chromosome was obtained using the systems or products sold in multilocus, methodologies recommended by the supplier and valid for analysis of DNA. We used the multilocus Identifiler and YFiler system of Applied Biosystems to the amplification of samples. The validation of results has shown a genetic profile in male anal secretion of the victims with a complete coincidence with the suspect. [Copyright &y& Elsevier]

Abstract: The haplotypes of seven Y-chromosome STR loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, and DYS393) were determined in a sample of 412 healthy and unrelated Brazilian males. A total of 264 different 7-loci haplotypes were identified, 210 of which were unique. The most frequent haplotype was detected in 31 instances, occurring with a frequency of 7.52%. The haplotype diversity was calculated as 98.83%. A haplotype with double peaks at the DYS389II locus and another with double peaks at DYS389I, DYS389II, and DYS439 were detected. [Copyright &y& Elsevier]

Abstract: In patrilineal societies, surnames and Y-specific haplotypes and haplogroups are expected to be correlated. This characteristic could help defining an initial pool of suspects in forensic genetics analysis. Here we evaluated this correlation in a sample of Central-Brazilian men. Surnames and Y-SNP haplogroup and Y-STR haplotype were analyzed in 55 pairs of Central-Brazilian men sharing surnames (n =110). Seven haplogroups and thirty-two haplotypes have been observed, none correlated solely to any of the twenty-eight surnames represented here. In this sample, two men with the same surname showed a chance of 0.41 of sharing a Y-specific haplogroup. This chance is higher for surnames of intermediate frequencies, whereas rare surnames show distinct chances as zero and one. Observed results may be over-estimated due to a predominance of a specific haplogroup (P92R7=49%) in the sample, what makes it possible for two men with no coancestry to share this haplogroup. Considering STR, only three pairs of men shared haplotypes. The average difference between the haplotypes in each pair was 2.45 mutational steps. This relatively low correlation is due to some historical and cultural peculiarities of the country, what makes it improper for forensic purposes in Brazil. [Copyright &y& Elsevier]

Y chromosome markers have been widely studied due to their various applications in the fields of forensic and evolutionary genetics. In this study, 35 Y-SNPs and 17 Y-STRs were genotyped in 253 males from the State of Espirito Santo, Brazil. A total of 18 haplogroups and 243 haplotypes were detected; the haplogroup and haplotype diversities were 0.7794 and 0.9997, respectively. Genetic distance analysis using the Y-STR data showed no statistically significant differences between Espirito Santo and other admixed populations from Brazil. The classification of paternal lineages based on haplogroups showed a predominant European contribution (85.88%), followed by African (11.37%) and Amerindian (2.75%) contributions.

Abstract: Through analysis of 15 Y-SNP markers by applying the SNaPshot (Applied Biosystems) method, this study revealed the genetic composition and origin of paternal lineages of 209 male individuals belonging to nine Afro-derived isolated communities in Alagoas, Brazil. [Copyright &y& Elsevier]

Abstract: This study provides population genetic data for individuals of Vitoria, Espirito Santo, Brazil, a location not yet characterized for STR frequencies used for genetic identification studies. Allelic frequencies and other population data analysis are reported for the 15 autosomal-STR loci included in the PowerPlex®16 kit (CSF1PO, D13S317, D16S539, D18S51, D21S11, D3S1358, D5S818, D7S820, D8S1179, FGA, Penta D, Penta E, TPOX, TH01 and vWA). Allele and haplotype frequencies, gene diversity and discrimination capacity were also estimated for the PowerPlex® Y System (DYS19, DYS385, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439). Blood samples were obtained from 226 unrelated volunteers (135 males and 91 females) residents in the city of Vitoria, representing a typical sample of the mixed ethnicity present in the Espirito Santo State, Brazil. Within the tested population, the total number of individuals typed for specific markers is: 226 for D13S317, D21S11, D3S1358, D7S820, D8S1179 and FGA; 225 for D16S539 and D5S818; 224 for D18S51; 223 for CSF1PO; 222 for Penta D and vWA; 220 for Penta E; 207 for TPOX and 142 for TH01. Y-STR haplotypes were analyzed for 102 unrelated males, being 71 of them present in the 135 autosomal-STR sample, and 31 new males tested only for Y-STR markers. All autosomal markers were in Hardy–Weinberg Equilibrium. Y-STR analysis identified 101 haplotypes, being 100 of them unique. [Copyright &y& Elsevier]

Abstract: A sample of 255 Brazilian males from Rio Grande do Sul (RS), the Brazilian southernmost state, was typed for 17 Y-STR loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, YGATA_H4.1 and DYS385ab). A total of 247 haplotypes were identified, of which 239 were unique and eight were found in two individuals each. The haplotype diversity (99.98%) and discrimination capacity (96.86%) were calculated. Pairwise haplotype distances showed that the RS population is not significantly different from Brazil, Rio de Janeiro, and Argentina, is different from São Paulo, Italy, and North Portugal, and is very distant from Spain, the Amazon region, Germany, and South Amerindians. When the RS data was separated in the seven geopolitical regions, some pairs of regions were significantly different; however no region was different from the whole Brazilian sample. [Copyright &y& Elsevier]

Background: Proechimys is the most diverse genus in family Echimyidae, comprising 25 species (two of which are polytypic) and 39 taxa. Despite the numerous forms of this rodent and their abundance in nature, there are many taxonomic problems due to phenotypic similarities within the genus and high intraspecific variation. Extensive karyotypic variation has been noted, however, with diploid numbers (2n) ranging from 14 to 62 chromosomes. Some heteromorphism can be found, and 57 different karyotypes have been described to date., Results: In the present work, we describe a cytotype with a very low 2n. Specimens of Proechimys cf. longicaudatus were collected from two different places in northern Mato Grosso state, Brazil (12°54″S, 52°22″W and 9°51'17″S, 58°14'53″W). The females and males had 16 and 17 chromosomes, respectively; all chromosomes were acrocentric, with the exception of the X chromosome, which was bi-armed. The sex chromosome system was found to be XY1Y2, originating from a Robertsonian rearrangement involving the X and a large acrocentric autosome. Females had two Neo-X chromosomes, and males had one Neo-X and two Y chromosomes. NOR staining was found in the interstitial region of one autosomal pair., Conclusions: Comparison of this karyotype with those described in the literature revealed that Proechimys with similar karyotypes had previously been collected from nearby localities. We therefore suggest that this Proechimys belongs to a different taxon, and is either a new species or one that requires reassessment.

Six populations of Hoplias malabaricus from the Lower Paranapanema River were studied and showed 2n = 40 with metacentric/submetacentric chromosomes for females and 2n = 39 with m/sm chromosomes for males, thereby revealing a multiple sex chromosome system of the X(1)X(1)X(2)X(2)/X(1)X(2)Y type. The Y chromosome was the largest metacentric chromosome in all karyotypes. The heterochromatic blocks were located in a pericentromeric region of all pairs and in telomeric regions in some other pairs. A conspicuous pericentromeric C-band was detected in a single pair, equivalent to the X(1) chromosome. No markers on X(2) chromosomes were detected, but they could be identified by their size. The females displayed the same distribution of C and chromomycin A(3) bands and 18S rDNA sites among the populations. However, the males exhibited differences in both number and position of Giemsa C-bands on the Y chromosome, which were also evident after Chromomycin A(3) banding and FISH with the 18S rDNA probe. These cytogenetic tools allowed for the identification of possible mechanisms involved in the differentiation and evolution of the Y chromosome., (2009 S. Karger AG, Basel.)

The collared peccary (Tayassu tajacu) is widely distributed over the American continent, being found from the south of the USA to the north of Argentina. In Brazil, it is spread all over the country, being one of the potential species to be raised in captivity. Therefore, the cytogenetic techniques could be a potential tool for reproductive monitoring of animals raised in captivity, mainly when destined for commercial purposes. This study had the objective of determining the chromosome number of two populations raised in captivity and characterizing them by GTG banding. For this purpose, an analysis was made of mitotic metaphases obtained from lymphocyte cultures made from blood samples of 11 animals, six of which from the Northeast and five from the North of Brazil. The results of this analysis showed the same karyotype pattern for the species (2n=30 chromosomes and NF=48), besides corresponding to the South American pattern of the species, i.e., without a translocation between autosomes 1 and 8, chromosome X acrocentric, and no differences were found between the two populations studied. However, chromosomal polymorphisms were observed compared to data from the literature on populations from North and South America.

The C-banding pattern and the size and location of the nucleolar organizer regions (NORs) are described for the first time in Brazilian populations of Anopheles (Nyssorhynchus) albitarsis sensu lato. C-banding revealed variation in the size of the centromeric heterochromatic blocks in autosomal chromosomes and in the acrocentric (X) and puntiform (Y) sex chromosomes. Fluorescence in situ hybridization showed that the NORs were located in the pericentromeric region of the sex (XX/XY) chromosomes and that this coincided with the number and location of centromeric constitutive heterochromatin blocks previously revealed by C-banding. The NORs varied in size among the homologues of the three populations. These findings of the populations studied support the hypothesis that the stability of NORs in the A. albitarsis complex is characterized by the presence of clustered and conserved sites in a unique pair of chromosomes.

Human identification can be accomplished by several technical procedures, especially by the comparative analysis of dental documents. Recent advances in molecular biology have now widened the scope for human identification and defined the protocols for the collection of biological material. Allele patterns of a population are particularly useful and they should be verified since they vary in different populations. We have studied the frequency of the alleles in three STR loci of the Y chromosome (DYS390, DYS391 and DYS393) in a group of Brazilian caucasian subjects. Results presented alleles 21, 22, 23, 24, 25 and 26 in locus DYS390, alleles 8, 9, 10, 11 12 and 13 in STR DYS391 and alleles in STR DYS393 were 11, 12, 13 14 and 15. The highest frequencies were 24 (0.46), 11 (0.37) and 13 (0.45). Each of the three STR systems had a PE (power of exclusion) of 0.6764 (DYS390), 0.5988 (DYS391) and 0.6136 (DYS393), The combination of the three STR systems revealed a PE of 0.9498, suggesting that this data can help in human identification.

This paper provides new data on chromosomes of Brazilian vampire bats Desmodus rotundus and Diphylla ecaudata. These species were analyzed by GTG, CBG- and CB-DAPI banding, AgNO3/CMA3 sequential staining, base-specific fluorochrome dyes and in situ hybridization with 18S rDNA probe. C-banding (CBG) revealed constitutive heterochromatin in the pericentromeric regions in all autosomes and the X and Y chromosomes appeared entirely heterochromatic in both species. CB-DAPI revealed a coincident banding pattern to that obtained by CBG. Triple staining CMA3/DA/DAPI revealed an R-banding and a weak G-banding pattern in the karyotypes. Sequential AgNO3/CMA3 staining showed a NOR located interstitially on the long arm of pair 8 in D. rotundus and on the short arm of pair 13 in D. ecaudata. FISH with a rDNA probe confirmed the location and number of NORs; a difference neither in intensity nor in size of hybridization signal was detected between homologues for both species.

The total genetic diversity of the Amerindian population is as high as that observed for other continental human populations because a large contribution from variation among tribes makes up for the low variation within tribes. This is attributed mainly to genetic drift acting on small isolated populations. However, a small founder population with a low genetic diversity is another factor that may contribute to the low intratribal diversity. Small founder populations seem to be a frequent event in the formation of new tribes among the Amerindians, but this event is usually not well recorded. In this paper, we analyze the genetic diversity of the Arara of Laranjal village and the Arara of Iriri village, with respect to seven tandem repeat autosomic segments (D1S80, ApoB, D4S43, vW1, vW2, F13A1 and D12S67), two Y-chromosome-specific polymorphisms (DYS19 and DYS199), and mitochondrial DNA (mtDNA) markers (restriction fragment length polymorphisms and sequencing of a segment of the D loop region). The occurrence of a single Y chromosome and mtDNA haplotype, and only 1-4 alleles of the autosomic loci investigated, corroborates historic and demographic records that the Arara of Iriri were founded by a single couple of siblings who came from the Arara of Laranjal, the largest group. Notwithstanding this fact, the genetic distance and the molecular variance between the two Arara villages were greater than those observed between them and other Amazonian tribes, suggesting that the microevolutionary process among Brazilian Amerindians may be misinterpreted if historic demographic data are not considered., (Copyright 2000 S. Karger AG, Basel.)

We analysed samples of Aedes aegypti from São José do Rio Preto and Franca (Brazil) by C-banding and Ag-banding staining techniques. C-banding pattern of Ae. aegypti from São José do Rio Preto examined in metaphase cells differed from Franca. The chromosomes 2, 3 and X showed centromeric C-bands in both populations, but a slightly stained centromeric band in the Y chromosome was observed only in São José do Rio Preto. In addition, the X chromosome in both populations and the Y chromosome of all individuals from São José do Rio Preto showed an intercalary band on one of the arms that was absent in Franca. An intercalary, new band, lying on the secondary constriction of chromosome 3 was also present in mosquitoes of both populations. The comparison of the present data with data in the literature for Ae. aegypti from other regions of the world showed that they differ as to the banding pattern of sex chromosomes and the now described intercalary band in chromosome 3. The observations suggested that the heterochromatic regions of all chromosomes are associated to constitute a single C-banded body in interphase cells. Ag-banding technique stained the centromeric regions of all chromosomes (including the Y) and the intercalary C-band region of the X chromosome in both populations. As Ae. aegypti populations are widespread in a great part of the world, the banding pattern variations indicate environmental interactions and may reveal both the chromosome evolutionary patterns in this species and the variations that may interfere with its vector activity.

A quantitative analysis of C bands by densitometric measurements in chromosomes 1, 9, 16, and Y was conducted in Caucasians and Japanese living in Brazil. Sixty normal unrelated subjects (30 males and 30 females) were studied in each racial group. Caucasians presented C bands of chromosomes 1, 9, and 16 larger than Japanese, but, on average, only the difference for C bands of chromosome 9 was statistically significant. In the Japanese, the C band sizes of chromosomes Y were, on average, significantly larger than in the Caucasians. The mean C band size of chromosome 9 and the sum of the three pairs were significantly larger in Caucasian than in Japanese males. The total values of constitutive heterochromatin, sigma (1qh,9qh,16qh,Yq12), did not show significant difference between Caucasian and Japanese males. The relative C band sizes of chromosomes 1, 9, and 16 were, on average, similar in Caucasians and Japanese. No sex difference was found in both racial groups. As regards the heteromorphism, only the values of C bands of chromosome 9 were, on average, significantly larger in Caucasians than in Japanese. Partial inversions were detected only among the Caucasians.

The C-bands of chromosomes 1, 9, 16 and Y of 434 individuals were measured using densitometry. The regression coefficients observed between the length of these regions and that of lq-h varied between 0.046 and 0.189, showing a clear size effect (the larger the band, the higher the contraction per unit size). Negative regressions between the band sizes of the autosomes and the time that elapsed between fixation and band induction were also observed as well as an effect of the treatment (in average, the CBG-bands were 17% larger than the CNG ones). Appropriate methods were developed to correct for these factors. Despite that, correlations between the heterochromatic regions of chromosomes 1, 9 and 16 remained significantly positive (0.15-0.24). The y distal heterochromatin showed the same rate of contraction as the others. But it was not influenced by the slide's age or the different methods of band induction. It showed no relationship, after correction, with the C-bands of chromosomes 1 and 9, but the correlation with those of chromosomes 16 remained positive (0.25 and 0.26).