MRPL53, a New Candidate Gene for Orofacial Clefting, Identified Using an eQTL Approach.

A valuable approach to understand how individual and population genetic differences can predispose to disease is to assess the impact of genetic variants on cellular functions (e.g., gene expression) of cell and tissue types related to pathological states. To understand the genetic basis of nonsyndromic cleft lip with or without cleft palate (NSCL/P) susceptibility, a complex and highly prevalent congenital malformation, we searched for genetic variants with a regulatory role in a disease-related tissue, the lip muscle (orbicularis oris muscle [OOM]), of affected individuals. From 46 OOM samples, which are frequently discarded during routine corrective surgeries on patients with orofacial clefts, we derived mesenchymal stem cells and correlated the individual genetic variants with gene expression from these cultured cells. Through this strategy, we detected significant cis-eQTLs (i.e., DNA variants affecting gene expression) and selected a few candidates to conduct an association study in a large Brazilian cohort (624 patients and 668 controls). This resulted in the discovery of a novel susceptibility locus for NSCL/P, rs1063588, the best eQTL for the MRPL53 gene, where evidence for association was mostly driven by the Native American ancestry component of our Brazilian sample. MRPL53 (2p13.1) encodes a 39S protein subunit of mitochondrial ribosomes and interacts with MYC, a transcription factor required for normal facial morphogenesis. Our study illustrates not only the importance of sampling admixed populations but also the relevance of measuring the functional effects of genetic variants over gene expression to dissect the complexity of disease phenotypes.

Impact of rare variants in ARHGAP29 to the etiology of oral clefts: role of loss-of-function vs missense variants.

Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a prevalent, complex congenital malformation. Genome-wide association studies (GWAS) on NSCL/P have consistently identified association for the 1p22 region, in which ARHGAP29 has emerged as the main candidate gene. ARHGAP29 re-sequencing studies in NSCL/P patients have identified rare variants; however, their clinical impact is still unclear. In this study we identified 10 rare variants in ARHGAP29, including five missense, one in-frame deletion, and four loss-of-function (LoF) variants, in a cohort of 188 familial NSCL/P cases. A significant mutational burden was found for LoF (Sequence Kernel Association Test, p = 0.0005) but not for missense variants in ARHGAP29, suggesting that only LoF variants contribute to the etiology of NSCL/P. Penetrance was estimated as 59%, indicating that heterozygous LoF variants in ARHGAP29 confer a moderate risk to NSCL/P. The GWAS hits in IRF6 (rs642961) and 1p22 (rs560426 and rs4147811) do not seem to contribute to the penetrance of the phenotype, based on co-segregation analysis. Our data show that rare variants leading to haploinsufficiency of ARHGAP29 represent an important etiological clefting mechanism, and genetic testing for this gene might be taken into consideration in genetic counseling of familial cases.

Oocistos deCryptosporidium parvum em fezes de bezerro infectado experimentalmente / Cryptosporidium parvum oocysts in the feces of experimentally infected calf

A dose of 5.0x106 Cryptosporidium parvum oocysts was inoculated in a newborn calf. After the inoculation, the feces were daily collected and the presence of oocysts was examined on slides using 0.17% green malachite dye. The total yield reached 1.5x1010 oocysts, with a peak production on the 7th day, confirming the infectious process and the role of calf infection in the potential risk for environmental contamination.

Situação epidemiológica da brucelose bovina no Estado de Goiás / Epidemiological status of bovine brucellosis in the State of Goiás, Brazil

Realizou-se um estudo para caracterizar a situação epidemiológica da brucelose no Estado de Goiás. O Estado foi estratificado em três circuitos produtores. Em cada circuito foram amostradas aleatoriamente 300 propriedades e, dentro dessas, foi escolhido de forma aleatória um número pré-estabelecido de animais, dos quais foi obtida uma amostra de sangue. No total, foram amostrados 10.744 animais, provenientes de 900 propriedades. Em cada propriedade visitada aplicou-se um questionário epidemiológico para verificar o tipo de exploração e as práticas de criação e sanitárias que poderiam estar associadas ao risco de infecção pela doença. O protocolo de testes utilizado foi o da triagem com o teste do antígeno acidificado tamponado e a confirmação dos positivos com o teste do 2-mercaptoetanol. O rebanho foi considerado positivo quando pelo menos um animal foi reagente às duas provas sorológicas. No estrato 1, a prevalência foi de 7,7 por cento [4,7-10,7 por cento] para propriedades, e de 1,4 por cento [0,99-1,7 por cento] para animais. No estrato 2, foi de 19,5 por cento [15,0-24,0 por cento] para propriedades e de 2,6 por cento [2,0-3,1 por cento] para animais. No estrato 3, foi de 21,4 por cento [16,7-26,1] para propriedades e 4,3 por cento [3,7-5,0 por cento] para animais. A prevalência obtida para o Estado foi de 17,5 por cento [14,9-20,2 por cento] para propriedades e de 3,0 por cento [2,7-3,3 por cento] para animais. Os fatores de risco (odds ratio, OR) associados à condição de foco, segundo a análise multivariada, foram: compra de reprodutores a comerciantes de gado (OR = 2,06 [1,12-3,52]), ocorrência de abortos nos últimos 12 meses (OR = 5,83 [3,86-8,8]) e prática de vacinação contra brucelose (OR = 2,07 [1,38-3,09]). Tanto a ocorrência de aborto quanto a vacinação são, neste caso, consequência da presença de brucelose no rebanho.

A study to characterize the epidemiological status of brucellosis in the State of Goiás was carried out. The State was divided in three regions. Three hundred herds were randomly sampled in each region and a pre-established number of animals was sampled in each of these herds. A total of 10,744 serum samples from 900 herds were collected. In each herd, it was applied an epidemiological questionnaire focused on herd traits as well as husbandry and sanitary practices that could be associated with the risk of infection. The serum samples were screened for antibodies against Brucella spp. by the Rose-Bengal Test (RBT), and all positive sera were re-tested by the 2-Mercaptoethanol test (2-ME). The herd was considered positive if at least one animal was positive on both RBT and 2-ME tests. For region 1, the herd prevalence was 7.7 percent [4.7-10.7 percent] and the animal prevalence was 1.4 percent [0.99-1.7 percent]. For region 2, the herd prevalence was 19.5 percent [15.0-24.0 percent] and the animal prevalence was 2.6 percent [2.0-3.1 percent]. For region 3, the herd prevalence was 21.4 percent [16.8-26.1 percent] and the animal prevalence was 4.3 percent [3.7-5.0 percent]. For the whole state, the herd prevalence was 17.5 percent [14.9-20.2 percent] and the animal prevalence was 3.0 percent [2.7-3.3 percent]. The multivariate analysis identified the following risk factors (odds ratio, OR) associated with positive herds: purchase of breeding stock from cattle traders (OR = 2.06 [1.12-3.52]), occurrence of abortions over the last 12 months (OR = 5.83 [3.86-8.8]), and vaccination against brucellosis (OR = 2.07 [1.38-3.09]). Both the abortions and the vaccination are, in this case, a consequence of the herd being infected with brucellosis.

Accumulative sodium poisoning in Brazilian swine fed whey.

Fifty 3-4-mo-old piglets died of accumulative sodium poisoning, but none of the 60 adult pigs with the same feeding and management did. The average ambient temperature throughout the period was 32 C. The herd had been regulary fed whey, ground corn and vegetables, but for at least 2 d the pigs were deprived of water and then water was offered ad libitum. Twenty hours later 20 piglets had died and the remaining exhibited classical nervous signs and died within 14 h. Only the piglets had a high degree of dehydration caused by water deprivation and exacerbated by the high average ambient temperature. Pulmonary edema was evident in most piglets. Acute cerebral edema and meningoencephalitis were present in all animals, but there was no polioencephalomalacia. The sodium accumulation was caused by the continuing intake of whey which contained 10,810 mg sodium/L. To produce the whey, 2 kg of sodium chloride had been added to every 100 kg of milk.

Botulism outbreak associated with poultry litter consumption in three Brazilian cattle herds.

One hundred fifty-five of 201 cattle from 3 different farms showed clinical signs and died of botulism after eating the same batch of poultry litter contaminated with poultry and rodent carcasses. The cattle had access to poultry litter for only 1 d; afterwards it was removed from the diet. Death occurred over a period of 17 d after the poultry litter intake. The peak mortality was on day 4; 20 animals died within 10 d of the ingestion. The greater the intake of poultry litter, the higher the cattle mortality. Three steers which died on the first day had peracute effects while the remaining cattle showed classical signs. Twenty-five of the 46 surviving cattle had mild clinical signs, but recovered in a few days. Type C Clostridium botulinum toxin was found in extracts of the poultry litter, carcasses and cattle intestinal contents. Nutrient composition of the poultry litter was normal but pH was lower (6.9) than usual (7.5 to 9.3).