ABSTRACT
Polymorphisms in a number of genes have consistently been associated with type 2 diabetes in various Caucasian populations. Little, however, is known of the association between these genetic risk markers and type 2 diabetes in sub-Saharan African subjects. The aim of the current study was to determine the association between common variants in the PPARG, KCNJ11, TCF7L2, FTO and HHEX genes in African (black) subjects of Zulu descent in KwaZulu-Natal, South Africa. The association between type 2 diabetes and rs1801282 (PPARG), rs5215 (KCNJ11), rs12255372 (TCF7L2), rs7903146 (TCF7L2) rs9939609 (FTO) and rs1111875 (HHEX) was determined in 178 South African Zulu subjects and 200 healthy ethnically matched control subjects. rs1801282 (PPARG) and rs5215 (KCNJ11) were not found to be present in either the subjects with type 2 diabetes or the control subjects. No association between rs12255372 (TCF7L2), rs9939609 (FTO) and type 2 diabetes was found. Heterozygosity at rs7903146 (TCF7L2) was associated with type 2 diabetes (odds ratio 1.84, 95% confidence interval: 1.192.83, p=0.0035). Decreased frequency of homozygosity for the common allele at rs7903146 (TCF7L2) was observed in subjects with type 2 diabetes (odds ratio 0.54, 95% confidence interval: 0.340.84; p=0.0043). There was an increased frequency of C allele homozygosity in subjects with type 2 diabetes at rs1111875 (HHEX), of borderline significance (odds ratio 1.54, 95% confidence interval 0.972.44, p=0.052). Subjects with type 2 diabetes harbouring one or more of the risk alleles did not differ from those without genetic variation at the loci studied, with respect to age at diagnosis, blood pressure, body mass index or serum lipid levels. We conclude that risk polymorphisms identified in Caucasian populations are not associated with type 2 diabetes in this group of South African subjects of Zulu descent, with the exception of rs7903146 (TCF7L2). The genetic risk for type 2 diabetes in sub-Saharan African subjects may reside in other, as yet unidentified, genes
Subject(s)
Black People , Polymorphism, GeneticABSTRACT
Purpose. Neurosyphilis is an uncommon disease. Although syphilis may promote the transmission of HIV the converse may not be true. The neuro-radiology of neurosyphilis is limited to two case series and several case reports. Our series of patients were reviewed to describe the clinical and radiological findings. Method. A retrospective chart review from 1994 to 2005 was done and demographic; clinical; laboratory and radiological findings were extracted. Patients HIV status was also recorded. Patients who satisfied the criteria for the diagnosis of neurosyphilis with the exclusion of alternate diagnoses were included. Results. Fifty-three patients were evaluated but only 41 charts were available for review. Thirty-nine of these had radiological data. The clinical spectrum included asymptomatic patients; strokes; dementia; cranial nerve palsies; spinal cord syndromes and polyradiculopathy. Imaging changes included normal findings; infarcts; meningeal based mass lesions; spinal intra-medullary hyper-intensities; cranial nerve enhancement and intra-medullary enhancing mass lesions. There was no difference in CSF cellular or chemistry findings between those with neurosyphilis who were HIV positive and those who were HIV negative. Amongst the patients where follow up was available most improved regardless of HIV status. Conclusion. Neurosyphilis has protean manifestations and can affect any central neurological system. The pathogenesis varies from inflammatory mass lesions to vascular occlusion and inflammatory damage. Syphilis should be an aetiological consideration in any neurological presentation where another cause is not obvious. The radiological features are not specific and would be seen with many inflammatory aetiologies affecting the CNS. The CSF picture is similar regardless of HIV status and patients should be managed similarly regardless of their HIV status