RESUMO
Las diarreas y enteropatías congénitas (CODE por su sigla en inglés) son un grupo de trastornos monogénicos que se han descrito en los últimos años. Dentro de las CODE, la mutación del gen de la diacilglicerol o-aciltransferasa 1 (DGAT1) es un trastorno enzimático poco común asociado con diarrea crónica grave de aparición temprana. El objetivo es presentar a dos hermanas que consultaron por diarrea crónica, retraso en el crecimiento, vómitos e hipoalbuminemia en la primera infancia. En ambas pacientes se encontró un compuesto heterocigota de la mutación del DGAT1. Esta mutación se describió previamente en la población asiática; sin embargo, estas son las dos primeras pacientes en tener esta mutación en la población latinoamericana. Estos dos casos pueden ampliar nuestro conocimiento sobre las diarreas congénitas en general y las características clínicas de los pacientes con mutaciones en DGAT1 en particular.
Congenital diarrhea and enteropathies (CODEs) are a group of monogenic disorders that have been described in recent years. Within the CODEs, the mutation in the diacylglycerol O-acyltransferase 1 (DGAT1) gene is a rare enzyme disorder associated with severe, early-onset chronic diarrhea. Our objective is to describe the case of 2 sisters who consulted for chronic diarrhea, growth retardation, vomiting, and hypoalbuminemia in early childhood. A compound heterozygous DGAT1 mutation was found in both patients. This mutation was previously described in the Asian population; however, these are the first 2 patients to show this mutation in the Latin American population. These 2 cases may expand our knowledge about congenital diarrhea in general and the clinical characteristics of patients with DGAT1 mutations in particular.
Assuntos
Humanos , Feminino , Lactente , Pré-Escolar , Diacilglicerol O-Aciltransferase/genética , Insuficiência de Crescimento/genética , Diarreia , MutaçãoRESUMO
Recent reports identified DGAT1 (EC 2.3.1.20) harboring a lysine to alanine substitution (K232A) as a candidate gene with a strong effect on milk production traits. Our objective was to estimate the frequency of the DGAT1 K232A polymorphism in the main Zebu and Taurine breeds in Brazil as well as in Zebu x Taurine crossbreds as a potential QTL for marker-assisted selection. Samples of 331 animals from the main Brazilian breeds, Nellore, Guzerat, Red Sindhi, Gyr, Holstein, and Gyr x Holstein F1 were genotyped for DGAT1 K232A polymorphism (A and K alleles) using the PCR-RFLP technique. The highest frequency of the A allele was found in the Holstein sample (73%) followed by Gyr x Holstein F1 (39%). Gyr and Red Sindhi showed low frequencies of A alleles (4 and 2.5%, respectively). The A allele was not found in the Nellore and Guzerat samples. Our results could be used to guide association studies between this locus and milk traits in these breeds.
Assuntos
Animais , Masculino , Feminino , Bovinos/genética , Diacilglicerol O-Aciltransferase/genética , Leite/química , Polimorfismo Genético/genética , Locos de Características Quantitativas/genética , Brasil , Cruzamento , Frequência do Gene , Marcadores Genéticos , Genótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de RestriçãoRESUMO
The ancestors of Uruguayan Creole cattle were introduced by the Spanish conquerors in the XVII century, following which the population grew extensively and became semi-feral before the introduction of selected breeds. Today the Uruguayan Creole cattle genetic reserve consists of 575 animals. We used the tetra primer amplification refractory mutation system polymerase chain reaction (ARMS-PCR) to analyze the kappa-casein, beta-casein, alphaS1-casein and alpha-lactoalbumin gene polymorphisms and restriction fragment length polymorphism PCR (RFLP-PCR) for the beta-lactoglobulin and the acylCoA:diacyl glycerol acyltransferase 1 (DGAT1) genes. The kappa-casein and beta-lactoglobulin genes presented very similar A and B allele frequencies, while the alphas1-casein and alpha-lactoalbumin gene B alleles showed much higher frequencies than the corresponding A alleles. The beta-casein B allele was not found in the population sampled. There was a very high frequency of the DGAT1 gene A allele which is associated with low milk fat content and high milk yield. All loci were in Hardy-Weinberg equilibrium and the level of heterozygosity agreed with the high genetic diversity observed in a previous analysis of this population. Preservation of the allelic richness observed in the Uruguayan Creole cattle should be considered for future dairy management and livestock genetic improvement. The results also emphasize the value of the tetra primers ARMS-PCR technique as a rapid, easy and economical way of genotyping cattle breeds for milk gene single nucleotide polymorphisms.
