Association between MUC1 gene polymorphism and expected progeny differences in Nelore cattle (Bos primigenius indicus)

MUC1 is a heavily glycosylated mammalian transmembrane protein expressed by mucosal secretory tissues for both protection against microbial infection and lubrication. An important characteristic of MUC1 is its variable number of tandem repeats (VNTR) containing several sites for O-glycosylation. VNTR length has been associated with many human diseases and with certain economically important traits in domestic ruminants. The aim of the present study was to correlate the length of MUC1 gene VNTR with expected progeny differences (EPDs) obtained for growth, fertility and carcass traits. Five alleles were identified, with alleles containing short VNTRs being more frequent than those with long, thereby demonstrating that Brazilian Nelore cattle are characterized by high frequencies in short MUC1 VNTRs. Statistical analyses revealed there to be no significant association between VNTR length and EPDs for weight at 120 days (W120), scrotal circumference at 365 (SC365) and 450 (SC450) days, age at first calving (AFC), and rib eye area (REA).

Widening the clinical spectrum of Pitt-Rogers-Danks/Wolf-Hirschhorn syndromes

Chromosomal rearrangements involving partial deletion of the short arm of chromosome 4 and partial duplication of the short arm of chromosome 8 have been described both in Pitt-Rogers-Danks syndrome (PRDS) and Wolf-Hirschhorn syndrome (WHS), the former being considered a milder phenotype of the latter. We describe a patient with partial deletion of chromosome 4 and partial duplication of chromosome 8 documented by array-comparative genomic hybridization (Array-CGH). In addition to the typical features of PRDS, the patient exhibited some clinical signs (genital hypoplasia, radioulnar synostosis and mesomelic limb shortness) infrequently, or never previously, reported in PRDS. These findings broaden the spectrum of anomalies generally associated with these syndromes.

Mitochondrial DNA single nucleotide polymorphism associated with weight estimated breeding values in Nelore cattle (Bos indicus)

We sampled 119 Nelore cattle (Bos indicus), 69 harboring B. indicus mtDNA plus 50 carrying Bos taurus mtDNA, to estimate the frequencies of putative mtDNA single nucleotide polymorphisms (SNPs) and investigate their association with Nelore weight and scrotal circumference estimated breeding values (EBVs). The PCR restriction fragment length polymorphism (PCR-RFLP) method was used to detect polymorphisms in the mitochondrial asparagine, cysteine, glycine, leucine and proline transporter RNA (tRNA) genes (tRNAasn, tRNAcys, tRNAgly, tRNAleu and tRNApro). The 50 cattle carrying B. taurus mtDNA were monomorphic for all the tRNA gene SNPs analyzed, suggesting that they are specific to mtDNA from B. indicus cattle. No tRNAcys or tRNAgly polymorphisms were detected in any of the cattle but we did detect polymorphic SNPs in the tRNAasn, tRNAleu and tRNApro genes in the cattle harboring B. indicus mtDNA, with the same allele observed in the B. taurus sequence being present in the following percentage of cattle harboring B. indicus mtDNA: 72.46 percent for tRNAasn, 95.23 percent for tRNAleu and 90.62 percent for tRNApro. Analyses of variance using the tRNAasn SNP as the independent variable and EBVs as the dependent variable showed that the G -> T SNP was significantly associated (p < 0.05) with maternal EBVs for weight at 120 and 210 days (p < 0.05) and animal's EBVs for weight at 210, 365 and 455 days. There was no association of the tRNAasn SNP with the scrotal circumference EBVs. These results confirm that mtDNA can affect weight and that mtDNA polymorphisms can be a source of genetic variation for quantitative traits.

Analysis of restriction fragment length polymorphism in the kappa-casein gene related to weight expected progeny difference in Nellore cattle

Restriction fragment length polymorphism (RFLP) has been detected at the bovine kappa-casein locus. The polymorphism has been analyzed for its effects in cattle production, mostly for milk traits and even for maternal effect on pre-weaning weights. We used polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) to genotype 408 Nellore animals for the non-silent mutation (Thr/Ile136 and Asp/Ala148) that characterizes the A and B variants of the polymorphism and compared expected progeny difference (EPD) for a maternal effect on 120 and 210 days weights and direct EPD for 120, 210, 450 and 550 day weight between AA and AB animals. The EPD values were obtained from the University of São Paulo (Brazil) Nellore Cattle Breeding Program, which evaluated 266,272 animals in 2001. Analysis of Variance was used to compare weight expected progeny differences (EPDs) between animals genotyped as AA and AB. The A allele frequency was 0.911. Although the AA animals had higher weight EPDs than AB animals the differences were not statistically significant (p > 0.05).

Use of the TSPY gene for sexing cattle

The Y-encoded, testis-specific protein (TSPY) is a Y-specific gene. The copy numbers of TSPY range from 20 to 60 in men and up to 200 in bulls. In this study, we examined the possibility of using the TSPY gene to sex cattle. DNA from blood samples of 100 Nelore cattle (50 males and 50 females) from the Nelore Cattle Breeding Program (PMGRN) was screened for TSPY by PCR using TSPY-specific primers. The assay was highly specific since all male samples were TSPY-positive and all female samples were negative. Positive results were also obtained at low DNA concentrations (less than 1 rhog/muL). These results showed that TSPY was a good male-specific marker, the usefulness of which was enhanced by the high copy number of the gene. This is the first report to demonstrate the applicability of TSPY for sexing cattle.

Trissomia 13 e pré-eclâmpsia / Trisomy 13 and preeclampsia

Um total de quatro recém-nascidos com trissomia 13 (80 por cento do total de casos) foi estudado retrospectivamente, assim como suas genitoras, no que concerne à associaçao entre trissomia 13 e pré-eclâmpsia. Os parâmetros analisados referiram-se aos dados de pré-natal concernentes aos níveis pressóricos, intercorrências clínico-obstétricas e idade materna. Para cada criança com trissomia 13, foram escolhidas, aleatoriamente, quatro crianças com cariótipo normal. A incidência de trissomias 13 mostrou-se discretamente elevada no nosso meio (1,4/10.000 recém-nascidos vivos). A idade materna dos recém-nascidos trissômicos mostrou-se significativamente mais, elevada que a do grupo-controle, condizente com os achados vigentes da literatura, onde a idade materna avançada é fator importante na etiologia das trissomias. A análise da série revelou associaçao entre gestaçoes com trissomia 13 e pré-eclâmpsia (p

Síndrome da insensibilidade androgênica: estudo comparativo entre as formas completa e incompleta / Androgen insensitivity syndrome: a comparative study between the complete and the incomplete forms

Com o objetivo de apresentar o perfil hormonal, a avaliaçäo diagnóstica e a conduta terapêutica na Síndrome da Insensibilidade Androgênica (SIA), realizamos um estudo de 15 pacientes, incluindo 10 com a forma completa e 5 com a forma incompleta. O diagnóstico foi firmado durante ou após a puberdade em 60 por cento dos casos. Gonadectomia bilateral foi realizada à época do diagnóstico na forma incompleta, e após a puberdade na forma completa. Estrogenioterapia foi mantida na puberdade após gonadectomia. Considerando o perfil hormonal, os níveis de LH estavam elevados em ambos os grupos, o FSH somente na forma incompleta e o E2, T e PRL. Após gonadectomia, o LH e FSH elevaram-se e a T diminuiu, significativamente.

46, XX, r (13)/46, XX, iso psu dic (13)? mosaicism

Os autores descrevem um caso raro de mosaicismo cromossômico 46,XX, r (13)/46, XX, iso psu dic (13)? em uma paciente que apresentava sinais clínicos semelhantes aos observados na síndrome do anel do cromossomo 13 (categoria 2a de Niebuhr, 1977). Discutem a hipótese de uma origem comum para as duas linhagens celulares e comparam os achados clínicos e citogenéticos aos descritos na literatura