No abstract

We used eight microsatellite loci to investigate the mating system in P. unifilis. DNA samples were collected from 66 hatchlings sampled from six nests on a central Amazon River beach near Barreirinha, Amazonas, Brazil. We found that P. unifilis females exhibited a promiscuous mating system (polyandry) with all nests being fathered by at least two males. The presence of multiple males contributing to each clutch was ascertained by the presence of at least two extra alleles in multilocus genotypes in each nest. Our data demonstrate that polyandry seems to be the prevalent system of mating in this endangered species.

Cytogenetic studies were conducted with Podocnemis expansa and Podocnemis sextuberculata, turtles of the Brazilian Amazon, aimed at a better characterization of the chromosomes of these species. To obtain mitotic chromosomes, lymphocytes were grown in a culture medium for karyotypes (RPMI), and harvested cells were treated to obtain metaphase chromosomes. The results showed the karyotypic number for P. sextuberculata and P. expansa to be 2n = 28 chromosomes; in both species the karyotypes included 5 pairs of macrochromosomes and 9 pairs of microchromosomes, that is, 16m + 2sm + 10a and NF = 46. Visualization of the nucleolar organizing region (NOR) in these two species was obtained by silver nitrate staining, and provided evidence of a simple NOR in the pericentromeric region of the fi rst chromosomal pair. The diploid number was found to be the same as that described in the literature but NOR data are described for the fi rst time.

We developed specific primers for microsatellite DNA regions of Podocnemis unifilis and tested their utility in population genetic and paternity studies on the species and other closely related Amazonian chelonians. Seventeen microsatellite loci were polymorphic in P. unifilis and all, plus two monomorphic microsatellites in P. unifilis, were polymorphic in at least one additional chelonian species, including Peltocephalus dumeriliana .

ABSTRACT. The genus Podocnemis comprises six living species, including P. erythrocephala (irapuca -red-headed river turtle). Data are available concerning the reproductive biology of the species of the genus Podocnemis, but little is known about their reproductive strategies. Considering the total lack of such data for P. erythrocephala, and with the goal of contributing information on their mode of reproduction, we examined the relationships among individuals of nests of this turtle, using microsatellite markers. Using four microsatellite loci, we analyzed the progeny in six nests from two localities in the Brazilian Amazon (Santa Isabel do rio Negro and Parintins). All juveniles from each nest were analyzed. The genotypes of each juvenile from each nest were identified, and because a sample of female DNA was not available, the maternal genotype was inferred from homozygous individuals in each nest. We found that this species is promiscuous; there was multiple paternity in five of the six nests analyzed. In addition to being important for the understanding of evolutionary and genetic processes, this type of information will be useful for chelonian management projects. Our data suggest one possible difference between reproductive patterns of the different populations. This multi-paternal condition may be a natural reproductive strategy for the preservation of the genetic diversity of this species.

O presente estudo buscou identificar a existência de anomalias cromossômicas registradas nos prontuários de nascidos vivos em uma maternidade. Estudo retrospectivo que analisou as informações contidas nos prontuários dos arquivos do Serviço de Arquivamento Médico de uma maternidade do estado do Amazonas entre janeiro de 2010 e dezembro de 2014, e estudou-se a correlação de anomalias cromossômicas presentes com características maternas e do nascido vivo. Analisou-se 15.621 prontuários, destes 163 apresentaram defeitos congênitos, 15 foram diagnosticados com síndromes cromossômicas distribuídas em três tipos de anomalias: 13 indivíduos com Síndrome de Down, um com Síndrome de Patau e um com Síndrome de Dany-Walker. Este é o primeiro registro de ocorrência e perfil dos nascimentos com anomalias cromossômicas em uma maternidade. O resultado é de grande importância para a saúde pública do Estado. A realização de novos estudos poderá fornecer um melhor panorama sobre diferentes doenças genéticas daquele estado.

The natural history of cervical cancer is strongly related to the presence of human papillomavirus (HPV) infection, with its relationship with cervical cancer being a matter of concern. It is estimated that 70% of all cervical cancers worldwide are caused by HPV 16 and 18. Accordingly, the present study aimed to contribute to the identification of HPV subtypes circulating in a group of women of Manaus-Brazil.  Cervical samples were collected from 49 women, following the eligibility criteria of the study, and DNA was then extracted from the samples, which were analyzed for the presence of the virus in the genetic material through the polymerase chain reaction (PCR) using generic primers (GP05/06). Finally, identification of the viral subtypes was performed using specific primers for the detection of the main subtypes already examined (16 and 18). Positive HPV DNA was detected in 100% of the samples included in the study. Human papillomavirus 16 was the most prevalent subtype in the majority of lesions, accounting for 29 (59.2%) of the positive cases, and HPV 18 was detected in four (8.2%) women. In these 4 cases there was co-infection, with the presence of both HPV 18 and HPV 16. Therefore, 40.8% (20 cases) in which HPV DNA was detected presented infection with other subtypes of HPV not included in the study. This data has clinical implications related to cervical cancer prevention, as the current prophylactic HPV vaccines are only effective against high-risk HPV 16 and 18 subtypes.

ABSTRACT. Genetic studies of multiple paternity are a valuable tool to gain information on the reproductive biology of turtles. We analyzed paternity type in Podocnemis sextuberculata and related number of fathers per nest to nesting period (beginning, middle, or end of nesting season); clutch size (number of eggs); female size; and hatchling success. Females were captured and maximum linear carapace lengths measured during the 60 days that encompass the nesting season at Rio Trombetas Biological Reserve (Pará, Brazil). Nests were marked and blood samples collected from hatchlings. Six heterologous loci were used: five from Podocnemis unifilis and one from Podocnemis expansa. Hatchlings were analyzed from 23 nests, and the rate of multiple paternity was 100%. The mean number of fathers per nest was six (± 0.9), and no significant difference between number of fathers in a nest and nesting period. Similarly there was no significant relationship between number of fathers in a nest and female size or hatchling success rate. Number of fathers was, however, positively correlated with clutch size (Spearman correlation rho = 0.47; P > 0.05). To our knowledge, this is the first study to test the relationship between multiple paternity and ecological aspects of the reproductive ecology of turtles in the genus Podocnemis.