Black South African Population Research Articles

Age at Diagnosis of Preinvasive and Invasive Cervical Neoplasia in South Africa: HIV-Positive Versus HIV-Negative Women

Human immunodeficiency virus-positive women develop invasive cervical cancer at a significantly earlier age than seronegative women. It is hypothesized that this might result from shorter preinvasive stages. Prospective observational study of histologically diagnosed 398 low-grade (LGSIL), 738 high-grade intraepithelial lesions (HGSIL), and 1048 invasive cancers (IC) in a black South African population. The study comprised of 493 (22.6%) seropositive women and 1691 (77.4%) seronegative women who served as the controls. All were subdivided into 5-years age bands. The mean age at diagnosis of LGSIL and HGSIL was similar in the cases (t = 0.7; P = 0.49) and the controls (t = 1.2; P = 0.22). The mean age at diagnosis of IC was significantly younger in the HIV-seropositive women than in the HIV-seronegative women (t = 14.0; P < 0.0001). The relative age distribution curves of LGSIL, HGSIL, and IC evolved close to each other in the cases. In the seronegative women, there was an 18-year lag between the peak age distribution of HGSIL and IC. Our data support the hypothesis of a shorter preinvasive stage in HIV-positive women.

Carotenoid and melanin pigment coloration affect perceived human health

The links between appearance and health influence human social interactions and are medically important, yet the facial cues influencing health judgments are unclear, and few studies describe connections to actual health. Increased facial skin yellowness (CIELab b*) and lightness ( L*) appear healthy in Caucasian faces, but it is unclear why. Skin yellowness is primarily affected by melanin and carotenoid pigments. Melanin (dark and yellow) enhances photoprotection and may be involved in immune defense, but may contribute to vitamin D deficiency. Carotenoids (yellow) signal health in bird and fish species, and are associated with improved immune defense, photoprotection and reproductive health in humans. We present three studies investigating the contribution of carotenoid and melanin to skin color and the healthy appearance of human faces. Study 1 demonstrates similar perceptual preferences for increased skin L* and b* in UK-based Caucasian and black South African populations. Study 2 shows that individuals with higher dietary intakes of carotenoids and fruit and vegetables have increased skin b* values and show skin reflectance spectra consistent with enhanced carotenoid absorption. Study 3 shows that, to maximize apparent facial health, participants choose to increase empirically derived skin carotenoid coloration more than melanin coloration in the skin portions of color-calibrated face photographs. Together our studies link skin carotenoid coloration to both perceived health and healthy diet, establishing carotenoid coloration as a valid cue to human health which is perceptible in a way that is relevant to mate choice, as it is in bird and fish species.

Triglyceride concentration and waist circumference influence alcohol-related plasminogen activator inhibitor-1 activity increase in black South Africans

We investigated the association between alcohol consumption and plasminogen activator inhibitor-1 activity (PAI-1act) and fibrinogen concentration in a black South African population presenting with lower PAI-1act and higher fibrinogen than what is typically observed in white populations. We, furthermore, wanted to investigate the effect of urbanization, sex, central obesity, increased triglycerides, 4G/5G polymorphism (PAI-1 only) and BMI on the association of alcohol with PAI-1act and fibrinogen. Data from 2010 apparently healthy, randomly collected black South African volunteers from the Prospective Urban and Rural Epidemiological (PURE) study were cross-sectionally analyzed. Alcohol consumption was recorded using quantitative food frequency questionnaires and fasting blood samples were collected for biochemical analysis including PAI-1act and fibrinogen. Heavy alcohol consumption is associated with significantly increased PAI-1act, in the total population as well as in the women separately, and tended to be so in men. This alcohol-related PAI-1act increase was observed in volunteers with increased triglycerides and central obesity but not in volunteers with normal levels and waist circumference. Urbanization, the 4G/5G polymorphism and BMI did not affect the association of alcohol with PAI-1act. Moderate alcohol consumption is associated with decreased fibrinogen concentration. Sex and level of urbanization did not affect the association of alcohol with fibrinogen. Fibrinogen decreased in normal and overweight volunteers but not in obese and centrally obese volunteers following moderate alcohol consumption. Triglyceride levels and waist circumference influence alcohol-related PAI-1act increase potentially through modulating adipocyte and triglyceride-induced PAI-1 production. Obesity prevented alcohol-related fibrinogen decrease possibly by counteracting the anti-inflammatory effect of moderate alcohol consumption.

Glutaric aciduria type 1 in South Africa—high incidence of glutaryl-CoA dehydrogenase deficiency in black South Africans

Glutaric Aciduria type 1 (GA 1) is an inherited disorder of lysine and tryptophan catabolism that typically manifests in infants with acute cerebral injury associated with intercurrent illness. We investigated the clinical, biochemical and molecular features in 14 known GA 1 patients in South Africa, most of whom were recently confirmed following the implementation of sensitive urine organic acid screening at our laboratory. Age at diagnosis ranged from 3days to 5years and poor clinical outcome reflected the delay in diagnosis in all but one patient. Twelve patients were unrelated black South Africans of whom all those tested (n=11) were found homozygous for the same A293T mutation in the glutaryl-CoA dehydrogenase (GCDH) gene. Excretion of 3-hydroxyglutarate (3-OHGA) was >30.1μmol/mmol creatinine (reference range <2.5) in all cases but glutarate excretion varied with 5 patients considered low excretors (glutarate <50μmol/mmol creatinine). Fibroblast GCDH activity was very low or absent in all of five cases tested. Heterozygosity for the A293T mutation was found 1 in 36 (95% CI; 1/54 - 1/24) unrelated black South African newborns (n=750) giving a predicted prevalence rate for GA 1 of 1 in 5184 (95% CI; 1/11664 - 1/2304) in this population. GA 1 is a treatable but often missed inherited disorder with a previously unrecognised high carrier frequency of a single mutation in the South African black population.

Adenomatoid odontogenic tumour: review of the literature and an analysis of 33 cases from South Africa

The adenomatoid odontogenic tumour (AOT) is a benign lesion of odontogenic origin. It is a slow growing tumour that results in a painless expansion of the jaws. This is a retrospective review of the demographic, clinical and radiographic features of AOTs diagnosed in a black South African population over 20 years. Of the 746 odontogenic tumours diagnosed, 4% were AOTs. The patients' ages ranged from 9 to 37 years with a mean age of 15 years. The highest incidence was in the second decade of life (85%). The female to male ratio was 5.6:1. The maxilla was more commonly affected than the mandible in a ratio of 1.5:1. The sizes of the lesions ranged from 2 to 7cm, with 60% involving an entire quadrant. All were of the central follicular type and appeared as well-demarcated radiolucent lesions. The canine was the most common impacted tooth. The treatment of choice was enucleation of the lesion, with no recurrences being reported.

The spectrum of HIV-associated cancers in a South African black population: results from a case-control study, 1995–2004

Accumulating evidence confirms different patterns of HIV-associated cancers in developed and developing countries. We report results of risk for specific cancers associated with HIV-1 infection from an on-going case control study started in government hospitals in Johannesburg in 1995. Cases consisted of cancers known or suspected to be associated with HIV infection: Kaposi sarcoma (n = 333), Non-Hodgkin lymphoma (n = 223), cancer of the uterine cervix (n = 1586), Hodgkin lymphoma (n = 154), cancers of anogenital organs other than cervix (n = 157), squamous cell skin cancer (n = 70), oral cavity and pharyngeal cancers (n = 319), liver cancer (n = 83), stomach cancer (n = 142), leukaemias (n = 323), myelomas (n = 189), melanoma (n = 53), lung cancer (n = 363) and sarcomas other than Kaposi (n = 93). The comparison group comprised 3,717 patients with all other cancer types and 682 patients with cardiovascular diseases. Odds Ratios (OR) were adjusted for age, sex, year of diagnosis, education level and number of sexual partners. Significantly increased risks associated with HIV-1 infection were found for Kaposi sarcoma (OR = 47.1, 95% CI = 31.9 – 69.8), Non-Hodgkin lymphoma (OR = 5.9, 95% CI = 4.3 – 8.1), cancer of the cervix (OR = 1.6, 95% CI = 1.3 – 2.0), Hodgkin lymphoma (OR = 1.6, 95% CI = 1.0 – 2.7), cancers of anogenital organs other than cervix (OR = 2.2, 95% CI = 1.4 – 3.3) and squamous cell skin cancers (OR = 2.6, 95% CI = 1.4 – 4.9). Our study results are supported by data from the pathology-based South African National Cancer Registry. In 2001 Kaposi sarcoma was recorded as the leading cancer in black males age 20 to 44 and in black females aged 20 to 29. From age 30, cervical cancers was the most common cancer diagnosed in black women. The above figures reflect HIV-related cancers prior to the public health sector roll-out of ART (anti-retroviral therapy), which began in 2005.

Differences in the Nature of Stroke in a Multiethnic Urban South African Population

The burden of stroke is increasing in Sub-Saharan Africa (SSA) as the population undergoes epidemiological and demographic transition. Little is known about the nature (risk factors, stroke type and subtype, and causes) of stroke in SSA and whether it differs from stroke in high-income populations. We aimed to compare the nature of stroke between black and white populations in South Africa. We used overlapping sources to ascertain consecutive first-ever-in-a-lifetime stroke patients admitted to Johannesburg Hospital over 23 months. We assessed each patient's demographic details, risk factors, CT confirmed pathological stroke type, ischemic stroke subtype and stroke severity, and compared the nature of stroke between black and white stroke patients. 524 patients with presumed stroke were referred. Of these, 432 were first-ever strokes; 308 patients were black and 76 white. Black patients were significantly younger (mean age 51) than white patients (61). Stroke severity was similar (median NIH stroke score 10; 95% CI 8 to 11). More black than white patients had cerebral hemorrhage (27% versus 15%), lacunar stroke (28% versus 22%) and total anterior circulation infarcts (28% versus 22%). Large vessel atherosclerosis (none detected) and ischemic heart disease were very uncommon (1%) as a cause of stroke in black patients. Hypertension (70% versus 68%) and diabetes (14 versus 15%) were as common in black and white stroke patients, but mean cholesterol levels were lower (4.6 mmol/L; 95% CI 4.3 to 4.9 versus 5.3 mmol/L; 4.8 to 5.7) and cigarette smoking less frequent in black patients (23 versus 54%). Although this was a hospital-based study, the difference in the nature of stroke between black and white stroke patients likely reflects the profile of stroke risk factors. There is an opportunity to prevent an otherwise inevitable increase in atherosclerotic stroke (and IHD) by targeting dietary and smoking habits in the black South African population.

The spectrum of human immunodeficiency virus‐associated cancers in a South African black population: Results from a case–control study, 1995–2004

The effect of the evolving HIV epidemic on cancer has been sparsely documented in Africa. We report results on the risk of cancer associated with HIV-1 infection using data from an ongoing study. A case-control analysis was used to estimate the relative risk (odds ratio, OR) of cancer types known to be AIDS defining: Kaposi's sarcoma (n = 333), non-Hodgkin lymphoma (NHL, n = 223) and cancers of the cervix (n = 1,586), and 11 cancer types possibly associated with HIV infection: Hodgkin lymphoma (n = 154), cancers of other anogenital organs (n = 157), squamous cell cancer of the skin (SCC, n = 70), oral cavity and pharynx (n = 319), liver (n = 83), stomach (n = 142), leukemia (n = 323), melanoma (n = 53), sarcomas other than Kaposi's (n = 93), myeloma (n = 189) and lung cancer (n = 363). The comparison group comprised 3,717 subjects with all other cancer types and 682 subjects with vascular disease. ORs were adjusted for age, sex (except cervical cancer), year of diagnosis, education and number of sexual partners. Significantly increased risks associated with HIV-1 infection were found for HIV/AIDS associated Kaposi's sarcoma (OR = 47.1, 95% CI = 31.9-69.8), NHL (OR = 5.9, 95% CI = 4.3-8.1) and cancer of the cervix (OR = 1.6, 95% CI = 1.3-2.0); Hodgkin's disease (OR = 1.6, 95% CI = 1.0-2.7), cancers of anogenital organs other than the cervix (OR = 2.2; 95% CI = 1.4-3.3) and SCC (OR = 2.6, 95% CI = 1.4-4.9) were also significantly increased. No significant associations were found between HIV and any of the other cancers examined. Risks for HIV-related cancers are consistent with previous studies in Africa, and are lower when compared to those observed in developed countries.

The Frequency of the H402 Allele of CFH and Its Involvement with Age-Related Maculopathy in an Aged Black African Xhosa Population

The H402 allele of the CFH gene is an established risk factor for age-related maculopathy (ARMD) in Caucasians, accounting for approximately 60% of the genetic risk at the population level. In general, the advanced forms of ARMD are rare in Black populations in Africa, as well as Black populations who have lived for generations in the United States or the West Indies, although there are reports that the earlier forms such as drusen may not be all that uncommon. The aim of the present study was to estimate the frequency of the C allele of the CFH Y402H variant in an aged South African Black Xhosa population and to describe the evidence of ARMD found.

Description of two new HLA‐C alleles in a Black South African population

Two new HLA-C alleles, Cw*0333 and Cw*0217, were identified in a Black South African population. HLA-Cw*0333 differs from Cw*030201 by an A-->G substitution at nucleotide 323, yielding an unusual missense substitution of Cys for the conserved Tyr-84 at the antigen cleft terminus. Molecular modeling suggests that this alters the predicted interactions of this critical residue with the opposite alpha(2)-helix, the peptide COOH terminus and possibly KIR2DL2. The second allele, Cw*0217, differs from Cw*0205 by an A-->T substitution at nucleotide 368, resulting in a Tyr-->Phe substitution at residue 99 of the HLA-C beta-pleated sheet that likely influences peptide side-chain binding. Both Cw*0333 and Cw*0217 appear to have arisen by missense mutations, respectively, from the HLA-B*5801-Cw*0302 and B*080101-Cw*0205 haplotypes.

Reevaluating the Health and Nutritional Status of Maize-Dependent Populations: Evidence for the Impact of Pellagra on Human Skeletons from South Africa

Pellagra, a niacin/tryptophan deficiency disease, is prevalent in populations that have high maize/low protein diets. Historically it has been essentially a disease of undernutrition and social inequality. We offer a unique analysis of both macro- and microstructural skeletal indicators from 31 individuals known to have died from pellagra (n = 14) and non-specific general malnutrition (n = 17). These cases are part of the Raymond Dart Skeletal Collection, housed at the University of Witwatersrand Medical School, Johannesburg, South Africa. This sample was drawn from a mid-to-late 20th century Black South African population. These individuals were found to exhibit a high incidence of alveolar bone loss, dental caries, enamel hypoplasias, periostitic lesions, osteomyelitis, cribra orbitalia, and cranial pitting. The frequency of specific pathological indicators separated the pellagrins from those with non-specific general malnutrition; however, the indicators were not pellagra-specific. We strongly argue that pellagra does affect bone in a noticeable way at both the macro- and micro-level, and therefore as a diet-related disease cannot be excluded as a possible cause for lesions seen in maize-dependent populations. We have also reported on the histological findings for rib samples taken from a subset of pellagra (n = 10) and general malnutrition (n = 14) cases. The critical difference between pellagrins and non-specific malnutrition cases was a decreased cortical area for pellagrins. Given its implications for interpreting the paleonutrition and paleopathology of prehistoric and historical transitions to maize intensive diets we present a checklist of macro- and micro-level indicators for investigating a signature pattern for the skeletal biology of pellagra. The overall synthesis of our findings provides new insights into skeletal-based interpretations of nutrition and micronutrient-related health problems for populations undergoing dietary transitions both past and present.

The molecular basis of Spinal Muscular Atrophy (SMA) in South African black patients

SMA is an autosomal recessive disorder that results in symmetrical muscle weakness and wasting due to degeneration of the anterior horns of the spinal cord. The gene for SMA, the survival motor neuron (SMN) gene is found on chromosome 5q13, in a region harbouring a 500 kb duplication, resulting in two copies (a telomeric and a centromeric) of each of the genes found within the duplication. SMN1 is homozygously deleted in approximately 95% of patients worldwide. Results of the current study show that only 51% (42/92) of South African black SMA patients have homozygous deletions of the SMN1 gene. This frequency is significantly lower than observed in the South African white patient group and in other international populations. The pattern of deletions in the South African black patients is also significantly different. In order to elucidate the molecular basis of SMA in the black population, a dosage assay enabling the detection of SMN1 deletion heterozygotes was independently developed. This assay confirmed SMN1 heterozygosity in at least 70% of black non-deletion SMA patients. However, no second disease-causing mutation or a common chromosomal background for this mutation could be identified in these patients. The frequency of SMA in both the black and white population was also determined using the SMN1 gene dosage assay. Results showed that SMA is more common than previously thought with carrier rates of 1 in 50 and 1 in 23 and a predicted birth incidence of 1 in 3574 and 1 in 1945 in the black population and the white population, respectively. Development and incorporation of the SMN1 dosage assay into the molecular diagnostic service will increase the percentage of cases in which the diagnosis of SMA can be confirmed and allow preclinical and prenatal diagnosis. Further gene characterisation and functional studies would need to be performed in order to further define the molecular basis of SMA in the South African black population.

Comparative study on the effect of ethnicity on wisdom tooth eruption

The current knowledge base for evaluating the influence of ethnic origin on wisdom tooth eruption is still inadequate. We therefore analyzed and compared the chronology of wisdom tooth eruption in three ethnic populations-German, Japanese, and black South African-based on evidence from 2,482 conventional orthopantomograms. The investigated German population ranked in the middle in terms of the age of wisdom tooth eruption. The black South African population was the fastest and the Japanese population the slowest in terms of reaching the respective eruption stages. Population-specific reference data should be used when evaluating wisdom tooth eruption for the purpose of forensic age estimation.

Protective effect against type 2 diabetes mellitus identified within the ACDC gene in a black South African diabetic cohort

Type 2 diabetes mellitus (T2D) is currently one of the fastest growing noncommunicable diseases in the world. It is induced by the pathogenic interaction between insulin resistance and secretion. This group of clinically heterogeneous disorders currently affects approximately 4% of the general population, but it is rapidly increasing, especially in developing regions such as sub-Saharan Africa. During this investigation, a diabetic (n = 227) and control cohort (n = 226) of adult black South African individuals were screened for the reported single nucleotide polymorphisms, termed C-11377G and G-11391A, within the promoter of the adiponectin ( ACDC) gene. Genotyping was achieved via a real-time polymerase chain reaction method. It was determined that the variant allele at G-11391A as well as the 12 haplotype was significantly associated with a protective factor with regard to T2D susceptibility. The low frequency of this variant within the cohorts investigated indicated a minor role in decreasing disease susceptibility. It may not be a significant disease risk factor in itself, but may assist in elucidating the mechanism of disease susceptibility. When compared to various non-African populations, it becomes apparent that the investigated single nucleotide polymorphisms have differential effects depending on the population investigated. This investigation therefore underscores the genetic heterogeneity at T2D susceptibility loci within the black South African population.

The relationship between anti-HPV-16 IgG seropositivity and cancer of the cervix, anogenital organs, oral cavity and pharynx, oesophagus and prostate in a black South African population

BackgroundHuman papillomavirus type 16 (HPV-16) infection is an important cause of cervical cancer, other anogenital cancers and, possibly, some oral and pharyngeal cancers. The association of HPV-16 with oesophageal and with prostate cancers has not been firmly established.MethodsWe analysed sera from 3,757 HIV seronegative black South Africans using an anti-HPV IgG enzyme-linked immunosorbent assay (ELISA). The subjects were recruited from 1995 to 2000 as part of an ongoing cancer case control study. Cases were patients with newly diagnosed cancers of the cervix (n = 946), other anogenital organs (n = 80), the oral cavity and pharynx (n = 102), the oesophagus (n = 369) or the prostate (n = 205). The comparison group consisted of 2,055 age and sex-matched patients randomly selected from the same data base, diagnosed at the same hospitals, but with a vascular disease or with a cancer unrelated to HPV infection. Subjects' sera were randomly and blindly allocated onto ELISA plates. Optical density (OD) levels of anti-HPV-16 IgG of > 0.45 and ≥ 0.767 were taken to be cut-offs for negative, medium and high antibody levels.ResultsAfter adjustment for potential confounders, cancer types that showed a statistically significant association with increased anti-HPV-16 IgG antibody (Ab) levels were cancer of the cervix (OR for medium Ab levels = 1.6, and for high = 2.4, p < 0.0001), cancers of other anogenital organs (OR for medium or high Ab levels = 2.5, p = 0.002), and cancer of the oesophagus (OR for medium Ab = 1.3, and high Ab levels = 1.6 p = 0.002). Cancers of the oral cavity and pharynx showed a borderline significant association in the unadjusted model (p = 0.05) but after adjustment for confounding the trend in relation to Ab levels was positive but not statistically significant (OR for medium Ab = 1.1, and high Ab = 1.5 p = 0.13). Prostate cancer was not associated with HPV-16 seropositivity (OR for medium Ab level = 1.4, and for high Ab level = 1.3, p = 0.3).ConclusionIf there is indeed an association between HPV-16 and oesophageal and possibly also some oral cavity and pharyngeal cancers, then emerging HPV vaccines may also reduce, at least in part, the incidence of these leading cancer types.

Body figure preference in South African adolescent females: a cross cultural study.

Eating disorders have traditionally been associated with the white community in South Africa. The emergence of eating disorders among blacks in the mid 1990's appeared to signal a demographic shift. Subsequent data suggested that eating disorders would increase in prevalence amongst black South Africans. The current study sought to explore body figure preference in a cross cultural South African sample, given the established relationship between body dissatisfaction and eating disorders. The sample comprised a community based, multi-racial adolescent population in both urban (n=1353) and rural (n=361) areas. The Body Figure Preference Test [BFPT] was administered. Most urban respondents had a desire to be smaller (white=72%; black=61%), whereas rural black respondents were more evenly divided amongst those who were content (31%), desiring to be larger (29%) and desiring to be smaller (40%) [Chi square value=105.309, df=4, p=0.001]. The findings of the study demonstrate that racial homogenization exists regarding body figure preference within the urban setting. Data from the rural area suggests milieu specific factors in this regard with fewer respondents desiring to be smaller. This may have implications for the emergence of eating disorders in black South African populations, more specifically those in urban areas.

The Impact of ACE Genotype on Serum ACE Activity in a Black South African Male Population

The strong association between the angiotensin I-converting enzyme (ACE) gene I/D polymorphism with serum ACE activity appears lacking in Nigerians and Kenyans, but has not previously been well assessed in others of African origin. This study addressed this issue in an ethnically well defined black South African population. A putative association for the A22982G ACE gene variant, a QTL likely to impact on serum ACE activity, was also sought. Subjects were 200 healthy male black South African volunteers from the Xhosa ethnic group. Venous blood was obtained from all subjects for DNA extraction. ACE I/D and A22982G genotypes were determined and serum ACE activity measured. Age and blood pressure were recorded. For the group as a whole (mean +/- SD age 38.5 +/- 9.8 years, SBP 119.6 +/- 14.1 mmHg, DBP 78.2 +/- 10.1 mmHg) serum ACE activity was 38.2 +/- 11.2 nmol ml(-1)min(-1). ACE I/D genotype was not significantly associated with serum ACE activity. In contrast, the A22982G variant was significantly associated with serum ACE activity, being 35.9 +/- 9.6, 38.1 +/- 10.6 and 42.4 +/- 15.3 nmol ml(-1)min(-1) for AA, AG and GG genotypes respectively; p = 0.03 by ANOVA and p = 0.01 by linear trend. In keeping with the findings in some other African populations, the ACE I/D polymorphism is not strongly associated with serum ACE activity in Xhosa South Africans. As such, it cannot be used as a marker of ACE activity in these subjects. In this regard the use of the A22982G gene variant may be more appropriate.

The frequency and anatomical features of torus mandibularis in a Black South African population

Torus mandibularis is a rounded bony protuberance on the lingual surface of the mandible and usually found above the myolohyoid line, medial to the molar roots. This report describes the frequency and morphology of torus and also proffers the likely cause among black South Africans. A total of 284 modern skeletal specimens were obtained from the Raymond Dart Collection of Human Skeletons at the School of Anatomical Sciences, University of the Witwatersrand. The mandibles were classified into dentate and edentulous, while those with torus, especially in dentate mandibles, were reviewed for side location, type and shape. No measurements were made, consistent with the view that these characteristics are non-metrical and should be assessed by means of a standard observatory procedure. Out of 246 dentate mandibles, 60 (24.4%) were found to have torus and only 1 (4.3%) out of the 23 male edentulous mandibles; the difference is statistically significant ( P=2.8%). The torus distribution among males and females was 48 (80%) and 12 (20%), respectively, and again statistically significant ( P< 0.05). Prevalence of torus was highest in the 40–60 years age group. The morphology of the torus showed that 37 (61.7%) were bilateral in location, 42 (70%) were of the solitary type and 31 (51.7%) were round in shape. The formation of torus follows the threshold model which holds that this is primarily a genetic trait, but with environmental factors such as mechanical stress necessary for its development.

Discriminating Sex in South African Blacks Using Patella Dimensions

For many years, sex determination has been carried out on skeletal remains to identify individuals in forensic cases and to assess populations in archaeological cases. Since it has been shown that not all bones are found in a forensic case, discriminant function equations should be derived for all bones of the body to assist in sex determination. Numerous studies have shown the usefulness of bones of the lower extremity (e.g. femur, tibia) in sex determination using discriminant function analysis, but the use of patella measurements has not been extensively investigated for this purpose. It is therefore the aim of this study to derive discriminant function equations for sex determination from measurements of the patella of South African blacks as represented in the Raymond A. Dart Collection of Human Skeletons. A total sample of 120 (60 male, 60 female) patellae were measured using six measurements. The Statistical Product and Service Solutions (SPSS) program was used to derive the equations. Stepwise and direct analyses were performed with the highest rate of classification of 85% thereby making the patella useful for sex determination. Thus, the proposed equations derived from this study should be used with caution and only on the South African black population group.

A radiological study of the rheumatoid hand in black South Africans.

To determine wrist and hand involvement in black South African patients with rheumatoid arthritis. Larsen scoring of the wrist and hand was done in 75 patients. The mean finger score was 9.67 (range 0 - 100) on the left hand and 10.3 (range 0 - 100) on the right. Scores for the wrists were 2.5 (range 0 - 5) for the left and 2.7 (range 0 - 5) for the right. Finger and thumb involvement were considerably less in the South African black population than in other series consisting mainly of white patients.