Jagged 1 Rescues the Duchenne Muscular Dystrophy Phenotype
Genotype/phenotypecorrelation studies suggest that the severity of the phenotype is dependent on the amount of muscle dystrophin or the siteof the mutation/deletion in the dystrophin gene ( Koenig et al., 1989; Passos-Bueno et al., 1994; Vainzof et al., 1990 ) DMD therapeutic approaches currently under development aim to rescue dystrophin expression in the muscle ( Fairclough et al., 2013 ). We looked for variants located under the association peak on chromosome 24 and focused on the Jagged1locus (including 3 KB upstream and downstream of the gene) in search for a variant present only in the escapers and not in theaffected GRMD dogs.
The affected group included the GRMD dogs that died before 5 years old withambulatory difficulties, respiratory failure, and cardiopathy; this group includes stillbirths, neonatal death, and one dog that was full ambulatory when he diedby ingesting a foreign object at 6-months-old (K2M11); all were confirmed to carry the GRMD mutation. The likelihood of the two escapers being identityby descent (IBD) at each SNP was estimated based on haplotype frequencies in the full pedigree using Beagle 4 (release v4.r1274) with default parametersettings ( Browning and Browning, 2007 ).
Weare extremely grateful for the extraordinary care and dedication of the veteri- narians Vivian Landini, Thais Andrade, and Erica Cangussu from the Instituteof Biosciences GRMD dogs kennel at the University of Sa˜o Paulo. Comparison of affected and escaper animals in the pedigree using the Illumina 170K canine arrayDNA from all GRMD dogs from the pedigree (Supplemental Figure 3) was isolated from blood and genotyped using the Illumina 170K canine HD array.
2 CellTiter 96 Non-Radioactive Cell Proliferation Assay (MTT – Promega) following
Development of a snapback method of single-strand conformation polymorphism analysis for genotyping Golden Retrievers for the X-linked muscular dystrophy allele. Zebrafish housing systems: a review of basic operating principles and considerations for design and functionality.