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Charcot-Marie-Tooth disease type 1A (CMT1A) is the most common heritable peripheral neuropathy and results from a duplication on chromosome 17 that results in an extra copy and increased dosage of peripheral myelin protein 22 (PMP22). Zhao et al., in this issue of the JCI, successfully utilized antisense oligonucleotides (ASOs) to reduce PMP22 and ameliorated neuropathy in both mouse and rat models of CMT1A. These data confirm that strategies to reduce PMP22 have potential as effective therapeutic approaches for CMT1A and lay the groundwork for clinical trials in humans afflicted with this chronic, debilitating neurodegenerative disease., Exciting news for CMT1A researchers Charcot-Marie-Tooth disease type 1A (CMT1A) is caused by a 1.4-Mb duplication on chromosome 17p11.2, which contains the peripheral myelin protein 22 (PMP22), a protein primarily [...]

Integration of the reverse-transcribed viral DNA into the host genome is an essential step in the life cycle of retroviruses. Retrovirus integrase catalyses insertions of both ends of the linear [...]

The aim of this study was to identify SNP markers that associate with variation in beef heifer reproduction and performance of their calves. A genome-wide association study was performed by means of the generalized quasi-likelihood score (GQLS) method using heifer genotypes from the BovineSNP50 BeadChip and estimated breeding values for pre-breeding body weight (PBW), pregnancy rate (PR), calving difficulty (CD), age at first calving (AFC), calf birth weight (BWT), calf weaning weight (WWT), and calf pre-weaning average daily gain (ADG). Data consisted of 785 replacement heifers from three Canadian research herds, namely Brandon Research Centre, Brandon, Manitoba, University of Alberta Roy Berg Kinsella Ranch, Kinsella, Alberta, and Lacombe Research Centre, Lacombe, Alberta. After applying a false discovery rate correction at a 5% significance level, a total of 4, 3, 3, 9, 6, 2, and 1 SNPs were significantly associated with PBW, PR, CD, AFC, BWT, WWT, and ADG, respectively. These SNPs were located on chromosomes 1, 5-7, 9,13-16,19-21, 24, 25, and 27-29. Chromosomes 1, 5, and 24 had SNPs with pleiotropic effects. New significant SNPs that impact functional traits were detected, many of which have not been previously reported. The results of this study support quantitative genetic studies related to the inheritance of these traits, and provides new knowledge regarding beef cattle quantitative trait loci effects. The identification of these SNPs provides a starting point to identify genes affecting heifer reproduction traits and performance of their calves (BWT, WWT, and ADG). They also contribute to a better understanding of the biology underlying these traits and will be potentially useful in marker- and genome-assisted selection and management. Key words: GWAS, SNP, allele substitution, genotypic effect, heifer reproduction, beef cattle. Le but de ce travail etait d'identifier des marqueurs SNP qui sont associes avec la variation pour la reproduction chez la genisse et pour la performance chez ses veaux. Une analyse d'association pan-genomique a ete realisee par une approche GQLS (<>) en employant les genotypes des genisses obtenus au moyen de la puce BovineSNP50 et en estimant la valeur genetique avant selection pour la masse corporelle (PBW), le taux de grossesse (PR), la difficulte de mise bas (CD), l'age a la premiere mise bas (AFC), masse du veau a la naissance (BWT), masse au sevrage (WWT), ainsi que le gain quotidien moyen avant sevrage (ADG). Les donnees ont ete obtenues aupres de 785 genisses de remplacement au sein de trois troupeaux de recherche, soit celui du Brandon Research Centre, Brandon, du University of Alberta Roy Berg Kinsella Ranch, Kinsella et du Lacombe Research Centre, Lacombe, Canada. Apres avoir applique une correction pour les faux positifs limitant ceux-ci a 5%, 4, 3, 3, 9, 6, 2 et 1 SNP ont montre une association significative avec le PBW, PR, CD, AFC, BWT, WWT et l'ADG respectivement. Ces SNP etaient situes sur les chromosomes 1, 5-7, 9,13-16,19-21, 24, 25 et 27-29. Les chromosomes 1, 5 et 24 portaient des SNP montrant des effets pleiotropiques. Des SNP significatifs inedits ayant un impact sur des caracteres d'interet ont ete detectes, plusieurs n'ayant jamais ete rapportes anterieurement. Les resultats de cette etude viennent appuyer des etudes anterieures en genetique quantitative sur ces memes caracteres et procurent un point de depart pour identifier des genes affectant les caracteres lies a la reproduction chez les genisses et la performance chez leurs veaux (BWT, WWT, ADG). Ils contribueront egalement il une meilleure comprehension de la biologie sous-tendant ces caracteres et seront potentiellement utiles pour pratiquer la selection assistee de marqueurs ou la selection genomique, de meme que pour la gestion des troupeaux. [Traduit par la Redaction] Mots-cles: GWAS, SNP, substitution d'alleles, effet genotypique, reproduction des genisses, bovin de boucherie., Introduction The development of replacement heifers for breeding is a significant expense for most cow-calf operations in the beef cattle industry. It is estimated to cost between $1000 and $1500 [...]