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Three outcrop localities and 28 onshore and offshore cores and wells were sampled from the east coast, Zululand and Durban Basins, the south coast onshore Algoa and the offshore Outeniqua Basins, and the west coast Orange Basin. Samples ranging in age from the Late Jurassic to the Late Cretaceous were examined for megafossils, microfossils, and fossnised wood to determine the first occurrence of angiosperms in southern Africa. In all three regions angiosperms first appear in the Aptian and they are represented by monosulcate, reticulate pollen genera, e.g. Clavatipollenites. Beginning in the Albian, tricolpate and tricolporate pollen types occur in low frequency with the monosulcate angiosperm pollen. This first occurrence of angiosperms in South Africa is more than 25 million years later than the earliest global appearance of angiosperms in the Middle East and north Africa. The concurrent presence of monosulcate and tri-aperturate pollen suggests that angiosperms migrated to South Africa via dispersal corridors and that angiosperms did not originate in southern Africa. [ABSTRACT FROM AUTHOR]

Few studies have considered the relationship between social capital and stigmatizing attitudes. The aim of this study is to assess the relationship between HIV stigmatizing attitudes and individual perceptions of social capital in South Africa. The study surveyed 619 community members to assess whether social capital predicted personal and attributed HIV stigmatizing attitudes. Personal stigma was defined as the individual's own attitude toward people with HIV and attributed stigma were those attitudes that the individual perceived as existing in their communities. Results showed that social capital components significantly predicted personal and attributed stigma above and beyond demographic covariates and whether the participant knew someone with HIV. Individual social capital components of empowerment, trust, and group membership related to personal stigma; and safety, trust, and homogeneity of residential area related to attributed stigma.

The purpose of this study was to examine the presentation of AIDS-related stigma and knowledge within the political context of the South African government's response to the AIDS epidemic. It was during the 2000 - 2004 period that key government officials publicly challenged the orthodox views of HIV/AIDS, with the South African president, Thabo Mbeki, actively positing the primary role of poverty and other socio-economic stressors in the progression of the AIDS epidemic. This discursive position had real-time effects for AIDS policy-making and ultimately delayed the implementation of a national antiretroviral (ARV) rollout programme. Consequently this position was criticised by commentators in the media and elsewhere for contributing to an already widespread climate of AIDS stigmatization and misinformation. To shed more light on these claims we conducted a survey in 2005 in Atteridgeville, a South African township, and compared results with those of a similar survey conducted shortly after ARV medications became available in 2004. Results indicated a reduction in AIDS stigma levels across the 1-year period, and that those participants who endorsed contentious political views (such as those expressed by key government officials) were more likely to have a higher level of AIDS-related stigma than those who disagreed. Nevertheless, this study cautions against drawing a causal relationship between the South African government's position and IDS-stigmatizing attitudes, and suggests that further political and social factors be accounted for in an attempt to gain a fuller understanding of this seemingly complex relationship.

The apparent low incidence of colon cancer in the Black population of South Africa has been ascribed to a non-Western diet. The present authors report the identification of two common 5-bp deletions at codons 1309 and 1061 of the adenomatous polyposis coli (APC) gene in a Xhosa and Zulu patient, respectively. The in vitro transcription/translation test (PTT) and a non-radioactive heteroduplex method, which facilitates resolution of enzymatically amplified DNA by agarose gel electrophoresis, were used for mutation detection. This study represents the first report of APC mutations in indigenous Black individuals clinically diagnosed with familial adenomatous polyposis coli (FAP). The two deletion mutations are responsible for FAP in 35% of affected South Africans, a frequency similar to that described in several other non-African populations. The apparently low incidence of colon cancer in the African population may be ascribed either to the rare occurrence of the 'second hit' needed for polyp formation or to a lower incidence of mutations in the APC gene.

Multiple sclerosis (MS) is believed to be an autoimmune process occurring in genetically susceptible individuals after an appropriate environmental exposure. We have exploited the homogeneous Afrikaner population of European ancestry to investigate the likelihood that iron dysregulation, in association with infectious and/or autoimmune disease susceptibility, may underlie the MS phenotype in a subgroup of patients. The functional Z-DNA forming repeat polymorphism of the natural resistance-associated macrophage protein-1 (NRAMP1) gene was analyzed in 104 patients diagnosed with MS and 522 Caucasian controls. A family-based control group consisting of 32 parental alleles not transmitted to MS offspring was additionally studied to exclude the likelihood of population substructures. Statistically significant differences in allelic distribution were observed between the patient and control samples drawn from the same population (P < 0.01). Evidence is furthermore provided that alleles considered to be detrimental in relation to autoimmune disease susceptibility may be maintained in the population as a consequence of improved survival to reproductive age following infectious disease challenge. Although it remains to be determined whether the disease phenotype in MS patients with allele 5 of the NRAMP1 promoter polymorphism is directly related to dysregulation of iron or modified susceptibility to viral infection and/or autoimmunity, a combination of these processes most likely underlies the disease phenotype in these patients. In view of the emerging role of polymorphic variants in complex diseases and minimizing of possible confounding factors in this association study, we conclude that allelic variation in the NRAMP1 promoter may contribute significantly to MS susceptibility in the South African Caucasian population., (Copyright 2001 Academic Press.)

Objective: To determine the molecular basis and establish a routine molecular diagnostic service for familial adenomatous polyposis coli (FAP) families in South Africa., Design: The coding region of the adenomatous polyposis coli (APC) gene in affected FAP kindreds was screened using heteroduplex analysis, single-strand conformation polymorphism analysis and the protein truncation test., Setting: Department of Human Genetics, University of Stellenbosch, and the Cancer Research Campaign Laboratories, Department of Pathology, University of Edinburgh and Molecular Medicine Centre, Western General Hospital, Edinburgh, Scotland (academic visit of 6 months)., Subjects: FAP-affected individuals and at-risk family members in 28 apparently unrelated South African families., Results: A total of nine different APC mutations was identified, allowing DNA-based diagnosis in 20 families. Three of these mutations have not been described previously in other populations., Conclusion: Pre-symptomatic diagnosis using direct mutation detection is cost-effective and surgical intervention has the potential to prevent cancer in at-risk individuals from FAP families.

A novel mutation at codon 441 in exon 10 of the adenomatous polyposis coli (APC) gene was identified in a South African family of mixed ancestry, using a convenient, non-radioactive, heteroduplex-SSCP screening assay. This single thymidine deletion after nucleotide position 1322 creates a frameshift resulting in a downstream stop codon at amino acid residue 453 of the APC gene. Genotypes of nine family members were subsequently correlated with the presence or absence of congenital hypertrophy of the retinal pigment epithelium (CHRPE), since expression of this common extracolonic manifestation of FAP is largely determined by the length of the truncated protein. CHRPE was absent in the five unaffected family members analysed, while four mutation positive subjects showed these ophthalmic lesions. Correlation between the molecular analysis and ophthalmic examinations, performed without knowledge of clinical and genetic status respectively, provided additional evidence in favour of the view that the range of phenotypic expression in FAP may result from different allelic manifestations of APC mutations.

To assess the value of DNA markers for the diagnosis of familial adenomatous polyposis (FAP) in South Africa, two highly informative CA-repeat polymorphisms (LNS CA-repeat in D5S346 and YN5.64c CA-repeat in D5S82) flanking the adenomatous polyposis coli (APC) gene, and three intragenic restriction fragment length polymorphisms (RFLPs) (exon 11/RsaI, exon 15.11/MspI, 3'UTR/SspI), were used for haplotype analysis in 13 South African families with the disease. The combination of these polymorphic markers proved to be highly informative and allowed an accurate diagnosis of FAP in 34/35 of the at-risk individuals analysed. Indirect molecular screening can therefore provide a comprehensive pre-clinical diagnostic test for FAP in South Africa. No predominant haplotype was found to be associated with FAP within the South African population. This suggests the absence of founder-type mutations in affected families and therefore marker studies remain important for the pre-clinical diagnosis of FAP in South Africa.

Haplotype association studies were performed in 10 unrelated South African families and 1 German immigrant family with familial adenomatous polyposis (FAP). Three DNA probes, recognising five restriction fragment length polymorphisms (RFLPs) around the gene locus for FAP on chromosome 5q, were used. The RFLP analysis was informative or partially informative in all the families studied. Five haplotypes were found to segregate with the disease locus. The predominant association of two of these haplotypes with FAP in the South African families suggests that two mutations may cause the disease in about 70% of families in this population. Meiotic recombination events were detected between the FAP gene and probe M4 (D5S6), but not probes Pi227 (D5S37) and C11p11 (D5S71). Haplotype analysis allowed the preclinical diagnosis of FAP in 5 subjects.

We report the occurrence of a common five-nucleotide deletion at codon 1309 of the adenomatous polyposis coli (APC) gene in four different South African population groups. The mutation causes familial adenomatous polyposis (FAP) in 18% (4/22 unrelated patients screened) of affected South Africans, which is similar to the frequency described in several other populations. Knowledge of the gene mutation underlying FAP enabled conclusive genetic testing of at-risk family members of four index patients in which this specific mutation has been characterized. The non-radioactive heteroduplex method described in this study allowed cost-effective molecular diagnosis directly after electrophoresis of enzymatically-amplified DNA in agarose gels. The resulting reduction of uncertainty for at-risk relatives is an important benefit of diagnosis at the DNA level.

A consulting service in geriatric medicine was established at Groote Schuur Hospital on 1 November 1981. The first 100 patients referred were compared with 100 patients of 65 years of age and over, selected randomly from the wards from which the referrals were coming, with a view to identifying characteristics of the geriatric patient appropriate to local needs. The findings are discussed against a background of the requirements for adequate care of the elderly, the need to teach geriatric medicine to those whose functions include care of the elderly, and some of the wider social implications in ensuring as equitable a distribution of service as possible. In conclusion a definition of the geriatric patient is offered.