Opposites attract: MHC-associated mate choice in a polygynous primate.

We investigated reproduction in a semi-free-ranging population of a polygynous primate, the mandrill, in relation to genetic relatedness and male genetic characteristics, using neutral microsatellite and major histocompatibility complex (MHC) genotyping. We compared genetic dissimilarity to the mother and genetic characteristics of the sire with all other potential sires present at the conception of each offspring (193 offspring for microsatellite genetics, 180 for MHC). The probability that a given male sired increased as pedigree relatedness with the mother decreased, and overall genetic dissimilarity and MHC dissimilarity with the mother increased. Reproductive success also increased with male microsatellite heterozygosity and MHC diversity. These effects were apparent despite the strong influence of dominance rank on male reproductive success. The closed nature of our study population is comparable to human populations for which MHC-associated mate choice has been reported, suggesting that such mate choice may be especially important in relatively isolated populations with little migration to introduce genetic variation.

High resolution array analysis: diagnosing pregnancies with abnormal ultrasound findings.

BACKGROUND: Genome-wide high resolution array analysis is becoming established as a diagnostic test in the investigation of individuals with learning disability and congenital anomalies; many novel microdeletion and microduplication syndromes have already been identified. The diagnostic use of high resolution array genomic hybridisation analysis for prenatal testing remains to be systematically assessed. METHODS: We studied 106 prenatal samples with abnormal ultrasound and a normal karyotype using the Affymetrix GeneChip 6.0 array. "Rare" DNA copy number variations (CNVs) were classified into three groups depending on their size, genomic location and the presence or absence of matched copy number changes in a large cohort of 3000 control samples analysed for copy number changes using genotyping arrays. RESULTS: A total of 35 rare CNVs were identified. 10 (9%) of these are considered likely to represent pathogenic CNVs; 5 were syndromic and 5 were novel. 12 CNVs were detected in at least one control hybridisation and likely to be benign, and 13 CNVs were of unknown clinical significance. In addition, we identified one case of cryptic mosaicism for trisomy 10, one case of loss of heterozygosity (LOH), and showed that the Affymetrix GeneChip 6.0 array platform can detect triploidy. CONCLUSIONS: We conclude that careful implementation of high resolution array testing would benefit at least 10% of obstetric patients with abnormal ultrasound findings and a normal karyotype result.

Musculocutaneous nerve palsy following traumatic spinal cord injury.

STUDY DESIGN: Case report of isolated musculocutaneous nerve lesion after an acute thoracic spinal cord injury. To our knowledge, this is the only reported case of isolated musculocutaneous nerve palsy associated with an acute spinal cord injury. OBJECTIVES: To determine the possible mechanisms of this isolated lesion. Also, to confirm the clinical diagnosis with a properly planned electrodiagnostic study. The differential diagnosis is considered. SUMMARY OF DATA: A comprehensive literature search was completed. Musculocutaneous lesions can be the result of heavy physical activity, shoulder subluxation, operative shoulder procedures, and intraoperative arm positioning. Isolated sensory lesions may be caused by carrying a heavy purse or phlebotomy. CONCLUSIONS: Intraoperative, position, traction injury and premorbid physical activity may be implicated in this patients nerve palsy.

Ulnar neuropathy resulting from diffuse intramuscular hemorrhage: a case report.

The ulnar nerve can be injured in the arm, forearm, and wrist. This report describes a 79-year-old woman who presented to the emergency department with acute lower extremity weakness and vertigo. Her medical history was significant for moderate to severe aortic stenosis, hypertension, and a remote intravascular thrombosis in the right forearm. The patient was diagnosed with a transient ischemic attack and was treated with anticoagulants. Three days after beginning anticoagulation therapy, she developed a diffuse intramuscular hemorrhage in the arm, which compromised predominantly ulnar fibers. The clinical, radiologic, and electrodiagnostic abnormalities are reviewed, and the possible etiologies of ulnar neuropathy are discussed. To our knowledge, this is the first report of ulnar neuropathy secondary to diffuse hemorrhage into the muscles of the arm.