HIV-1 epidemiology and circulating subtypes in the countryside of South Brazil

INTRODUCTION: Human immunodeficiency virus type 1 (HIV-1) has spread worldwide, with several subtypes and circulating recombinant forms. Brazil has an incidence of 20.5 HIV-1/acquired immunodeficiency syndrome (AIDS) patients per 100,000 inhabitants; however, the Southernmost State of Rio Grande do Sul (RS) has more than twice the number of HIV-1-infected people (41.3/100,000 inhabitants) and a different pattern of subtype frequencies, as previously reported in studies conducted in the capital (Porto Alegre) and its metropolitan region. This study examined HIV-1/AIDS epidemiological and molecular aspects in the countryside of Rio Grande do Sul. METHODS: Socio-demographic, clinical and risk behavioral characteristics were obtained from HIV-1-positive adult patients using a structured questionnaire. HIV-1 subtypes were determined by nested-polymerase chain reaction (PCR) and sequencing of the pol and env genes. RESULTS: The study sample included 149 (55% women) patients with a mean age of 41.8 ± 11.9 years. Most (73.8%) patients had a low education level and reported heterosexual practices as the most (91.9%) probable transmission route. HIV-1 subtypes were detected in 26 patients: 18 (69.2%) infected with subtype C, six (23.1%) infected with subtype B and two (7.7%) infected with BC recombinant forms. CONCLUSIONS: These data highlight the increasing number of HIV-1 subtype C infections in the countryside of South Brazil. .

Identification of molecular markers on bovine chromosome 18 associated to calving interval in a Brangus-Ibagé cattle herd

In the detection phase of a bovine marker assisted selection program, this paper investigated the genetic variability of three microsatellites on the chromosome 18 (BTA 18). The possible associations between genotypes or alleles of these markers versus weight at first calving and a lifetime calving interval (as indicators of reproductive performance) were evaluated in a beef cattle herd (5/8 Aberdeen Angus x 3/8 Nelore). Eleven alleles were detected in TGLA227 and ILSTS002 and three in BMS3004, the most frequent being TGLA227*79, ILSTS002*133, ILSTS002*135 and BMS3004*129. Polymorphic information content ranged from 0.41 to 0.84, while heterozygosity ranged from 49 percent to 86 percent, with an average value of 77 percent. The association analyses performed between genotype classes for the genetic markers versus weight at first calving indicated no significant result. Also, no correlation was observed between calving interval (CI) and TGLA227 genotypes. However, positive associations were detected between ILSTS002 and BMS3004 and CI. Animals carrying at least one ILSTS002*135 allele presented a CI about 39 days longer than the individuals with other genotypes; animals heterozygous for BMS3004 presented a CI about 35 days shorter than the homozygous. On these grounds, it can be concluded that these markers can be useful as an aid to fertility selection, in this herd.

Na fase de detecção, em um programa de seleção assistida por marcadores, em bovinos, este trabalho investigou a variabilidade genética de três microssatélites no cromossomo 18 (BTA 18). As possíveis associações entre genótipos ou alelos destes marcadores versus o peso ao primeiro parto e o intervalo entre partos (como indicadores do desempenho reprodutivo) foram avaliados em um rebanho de gado de corte (5/8 Aberdeen Angus x 3/8 Nelore). Onze alelos foram detectados em TGLA227 e ILSTS002 e três em BMS3004, os mais freqüentes sendo TGLA227*79, ILSTS002*133, ILSTS002*135 e BMS3004*129. O conteúdo polimórfico de informação variou de 0,41 a 0,84, enquanto a heterozigosidade variou de 49 a 86 por cento, com média de 77 por cento. As análises de associação efetuadas entre classes genotípicas dos marcadores genéticos versus o peso ao primeiro parto não indicaram resultados significantes. Da mesma forma, nenhuma correlação foi observada entre o intervalo entre partos (IEP) e os genótipos de TGLA227. Entretanto, associações positivas foram detectadas entre ILSTS002 e BMS3004 com o IEP. Animais portadores de pelo menos um alelo ILSTS002*135 apresentaram IEP cerca de 39 dias mais longo que os indivíduos com outros genótipos, e animais heterozigotos para BMS3004 apresentaram IEP cerca de 35 dias mais curto que os homozigotos. Assim, pode-se concluir que esses marcadores podem ser úteis como auxiliares na seleção para fertilidade, o rebanho em questão.

Association between molecular markers linked to the Leptin gene and weight gain in postpartum beef cows

Three short tandem repeats (STRs), BMS1074, BM1500, IDVGA-51, and three single nucleotide polymorphisms (SNPs), LEPSau3AI (A/B), LEPSau3AI (+/-) and LEPKpn2I linked to the LEP gene were investigated to verify associations with productive performance in postpartum cows of two beef cattle breeds, Aberdeen Angus (AA, n=98) and Charolais (C, n=83). After polymerase chain reaction, STRs were analyzed by vertical electrophoresis and SNPs in agarose gel after endonucleases cleavage. In AA herd 79 percent of BMS1074*151 carriers had a lower average daily weight gain (ADG) when compared with the population mean daily weight gain (103g), while 62 percent of BMS1074*151 non-carriers presented a higher ADG (P<0.01); AA animals with at least one BMS1074*151 allele showed a ADG about 159g lower than that of other animals (P<0.01). In both herds, carriers of the BM1500*136 allele presented higher ADG (about 75g day-1 higher in AA, P<0.05, and 96g day-1 in C, P<0.10); animals with one BM1500*136 allele had about a 3-fold higher chance of having a higher ADG than non-cariers, in both populations.

Foram investigadas três repetições curtas em tandem (STRs), BMS1074, BM1500 e IDVGA-51 e três polimorfismos de um único nucleotídeo (SNPs) LEPSau3AI (A/B), LEPSau3AI (+/-) e LEPKpn2I, ligados ao gene da leptina, verificando-se associações com o desempenho produtivo em vacas no pós-parto, em dois rebanhos de gado de corte, Aberdeen Angus (AA, n=98) e Charolês (C, n=83). Após a reação em cadeia da polimerase, os STRs foram analisados em géis de poliacrilamida e os SNPs em gel de agarose, após a clivagem com endonucleases. Na raça AA, 79 por cento dos portadores do alelo BMS1074*151 apresentaram ganho médio de peso diário (ADG) menor, quando comparados com a média da população (103g), enquanto 62 por cento dos não-portadores mostraram ADG mais alto (P<0,01); os animais AA com pelo menos um alelo BMS1074*151 possuem ADG cerca de 159g menor que os outros animais (P<0,01). Em ambos os rebanhos, portadores do alelo BM1500*136 apresentaram ADG mais alto (em torno de 75g dia-1 em AA, P<0,05 e 96g dia-1 em C, P<0,10) e animais com um alelo BM1500*136 possuem cerca de três vezes mais chance de ter um ADG maior que os não-portadores.