Genomic analysis of genetic markers associated with inherited cardiomyopathy (round heart disease) in the turkey (Meleagris gallopavo)

In turkeys, spontaneous cardiomyopathy or round heart (RH) disease is characterised by dilated ventricles and cardiac muscle hypertrophy. Although the aetiology of RH is still unknown, the disease can have a significant economic impact on turkey producers. In an initial attempt to identify genomic regions associated with RH, we utilised the chicken genome sequence to target short DNA sequences (sequence-characterised amplified regions, SCARs) identified in previous studies that had significant differences in frequency distribution between RH+ and RH- turkeys. SCARs were comparatively aligned with the chicken whole-genome sequence to identify flanking regions for primer design. Primers from 32 alignments were tested and target sequences were successfully amplified for 30 loci (94%). Comparative re-sequencing identified putative SNPs in 20 of the 30 loci (67%). Genetically informative SNPs at 16 loci were genotyped in the UMN/NTBF turkey mapping population. As a result of this study, 34 markers were placed on the turkey/chicken comparative map and 15 markers were added to the turkey genetic linkage map. The position of these markers relative to cardiac-related genes is presented. In addition, analysis of genotypes at 109 microsatellite loci presumed to flank the SCAR sequences in the turkey genome identified four significant associations with RH.

Assignment of linkage groups to turkey chromosome 1 (MGA1)

Previous genetic mapping identified three linkage groups (M1, M18 and M26) in the turkey corresponding to chicken chromosome 1 (GGA1). This is inconsistent with previously described chromosomal differences between these species. FISH analysis of BAC clones corresponding to microsatellite markers from each of the three turkey linkage groups, assigned all three linkage groups to a single chromosome (MGA1).

REM sleep enhancement by bupropion in depressed men

OBJECTIVE

The authors compared the effects of bupropion, fluoxetine, and cognitive behavior therapy on EEG sleep in depressed subjects.

METHOD

All-night sleep EEG studies were performed before treatment and after partial or full remission on 18 men with depression diagnosed according to Research Diagnostic Criteria and randomly assigned to treatment with either bupropion (N = 7) or fluoxetine (N = 11). Response to these drugs was measured by changes in Hamilton Depression Rating Scale scores. Pre- and posttreatment EEG sleep study results before and after treatment with cognitive behavior therapy were also available for 18 men matched in age and severity of Hamilton depression scale score, and one-time EEG sleep measures were available for 36 men who were not depressed.

RESULTS

REM latency was reduced and REM sleep percent and REM time increased after treatment in the depressed men given bupropion. These effects contrasted with the effects of fluoxetine and cognitive behavior therapy.

CONCLUSIONS

This study represents the first report of an antidepressant medication that shortens REM latency and increases REM sleep. If confirmed, this finding may require a revision of our current understanding of the relation among depression, REM sleep, and anti-depressant mechanisms.

The value of neuroradiology in infantile spasms

The results of neuroradiologic studies of 71 children with infantile spasms treated with ACTH were correlated with the developmental outcome at follow-up (mean 62 months, range 14 to 207 months). Fifty-two (73%) patients had an abnormal NRS on initial evaluation; 49% had cerebral atrophy, 18% had congenital anomalies, and 6% had hydrocephalus. Twenty patients were normal on initial clinical evaluation. At follow-up only the eight (40%) with normal NRS were normal. Twelve (60%) who had unexpected abnormalities on NRS were retarded at follow-up. CAT scanning is necessary to predict the developmental outcome in developmentally normal children with infantile spasm. Eight of nine patients with normal NRS in the early treatment group were developmentally normal at presentation and follow-up. Ten patients who were developmentally normal before spasms began, and had normal NRS but were in the late treatment group, were retarded at initial evaluation and follow-up. This finding suggests that early treatment of children who have a normal NRS and normal development at onset of spasm prevents mental retardation.