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1.
Hum Reprod Open ; 2022(3): hoac024, 2022.
Article in English | MEDLINE | ID: mdl-35747402

ABSTRACT

STUDY QUESTION: Are low or high plasma mannose-binding lectin (p-MBL) levels associated with recurrent pregnancy loss (RPL) and the reproductive and perinatal outcomes before and after RPL? SUMMARY ANSWER: The prevalence of low p-MBL levels was significantly higher in RPL patients, while high levels were significantly less prevalent. No association was found between p-MBL level and reproductive and perinatal outcomes before and after RPL. WHAT IS KNOWN ALREADY: Mannose-binding lectin (MBL) is an important component in the innate immune system. Low p-MBL levels have been associated with RPL, while the correlation with high levels has been poorly studied. Adverse perinatal outcomes are generally more frequent among RPL patients, but reports concerning the association between maternal p-MBL levels and perinatal outcomes, including birth weight (BW) and gestational age (GA), are conflicting. STUDY DESIGN SIZE DURATION: This study was a combined cross-sectional and cohort study of 267 RPL patients admitted to the RPL Center of Western Denmark between January 2016 and March 2020. RPL patients were followed until birth of a liveborn child or until end of follow-up, March 2021. A sample of 185 healthy female blood donors of reproductive age was used as a MBL reference group. PARTICIPANTS/MATERIALS SETTING METHODS: All RPL patients had ≥3 consecutive pregnancy losses, a regular menstrual cycle and no known significant chromosomal or uterine malformations. At the first consultation, routine blood samples including p-MBL measurement and detailed obstetrical and perinatal information were collected. p-MBL levels in RPL patients were compared to the MBL reference group. A logistic regression analysis adjusted for relevant confounders assessed the association between low p-MBL levels and an unsuccessful reproductive outcome in RPL patients in first pregnancy after admission. Perinatal outcomes before and after RPL were compared between RPL subgroups according to low (≤500 µg/l), intermediate (501-3000 µg/l) and high (>3000 µg/l) p-MBL levels. MAIN RESULTS AND THE ROLE OF CHANCE: Significantly more RPL patients had low p-MBL levels (prevalence proportion ratio (PPR): 1.79, 95% CI: 1.34-2.38) and fewer had high p-MBL levels (PPR: 0.56, 95% CI: 0.40-0.79) compared to the reference group, while the prevalence of intermediate p-MBL level was not different between the groups (PPR: 0.86, 95% CI: 0.69-1.08). In the prospective study, low p-MBL level was not a significant risk factor for a pregnancy loss in the first pregnancy after admission after adjustment for age, BMI and smoking. Neither before nor after the RPL diagnosis were maternal p-MBL levels significantly associated with BW or GA. LIMITATIONS REASONS FOR CAUTION: Only 161 (60.3%) patients had given birth after RPL during the follow-up period, which limited the possibility to detect clear associations between p-MBL levels and perinatal outcomes after RPL. WIDER IMPLICATIONS OF THE FINDINGS: In agreement with several previous studies, low p-MBL levels are strongly associated with RPL, while this study for the first time documents that high levels may play a protective role, which suggests a causal relationship. We suggest that larger prospective studies evaluate the association between p-MBL levels and RPL prognosis. STUDY FUNDING/COMPETING INTERESTS: No external funding was received. We acknowledge the Department of Obstetrics and Gynaecology at Aalborg University Hospital for financial support. U.S.K. has reported personal fees from Merck, consulting fees from IBSA Nordic, and a grant from Gedeon Richter, Merck and IBSA Nordic outside of the submitted work. TRIAL REGISTRATION NUMBER: ID from clinicaltrials.gov is NCT04017754.

2.
Diabetes int. (Middle East/Afr. ed.) ; 18(1): 12-16, 2010. tab
Article in English | AIM (Africa) | ID: biblio-1261176

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, Genetic
3.
Cardiovasc J S Afr ; 16(3): 152-7, 2005.
Article in English | MEDLINE | ID: mdl-16049588

ABSTRACT

BACKGROUND: The relationship between pro-coagulant gene polymorphisms, clinical features and the risk of premature coronary heart disease (CHD) in Indian Asian subjects resident in South Africa has been investigated. METHODS: The prevalence of the beta-fibrinogen -455G/A and -148C/T, and the factor VII 10 bp 5' promoter insertion/deletion and R353Q polymorphisms were examined in 195 unrelated Indian Asian patients (< or = 45 years) who presented with myocardial infarction (MI). Results were compared with those from 107 unaffected siblings (18-45 years) and 300 healthy age- and race-matched control subjects. RESULTS: Overall, none of the polymorphisms examined here showed any association with MI. However, when stratified according to obesity, patients with a BMI > 30 kg/m2 had a significantly higher frequency of the beta-fibrinogen variant alleles, compared with non-obese patients (19% vs 9%; p = 0.025) and controls (19% vs 9%; p = 0.003). Furthermore, the highest frequency of variant alleles occurred in obese smokers (24%), compared with 4% in non-obese non-smokers (p = 0.003) and 9% in control subjects (p < 0.001). The factor VII R353Q and promoter insertion variants, on the other hand, were associated with higher HDL and lower LDL levels (p = 0.034 and 0.04, respectively). CONCLUSION: In young Indian Asians who are both obese and smoke, the beta-fibrinogen genetic polymorphisms -455G-->A and -148C-->T, which are in linkage disequilibrium, are significant risk factors for the development of MI. Factor VII genetic variants, namely the 10 bp promoter insertion/deletion and R353Q polymorphisms, may possibly play a protective role through their association with elevated HDL and low LDL levels, respectively.


Subject(s)
Blood Coagulation/genetics , Myocardial Infarction/ethnology , Myocardial Infarction/genetics , Polymorphism, Genetic , Adolescent , Adult , Biomarkers/blood , Case-Control Studies , Factor VII/genetics , Factor VII/metabolism , Fibrinogen/genetics , Fibrinogen/metabolism , Gene Frequency , Genetic Predisposition to Disease , Genotype , Humans , India/ethnology , Lipoproteins, HDL/blood , Lipoproteins, HDL/genetics , Lipoproteins, LDL/blood , Lipoproteins, LDL/genetics , Middle Aged , Obesity/ethnology , Obesity/genetics , Risk Factors , Smoking/ethnology , Smoking/genetics , South Africa/epidemiology , South Africa/ethnology , Ventricular Function, Left/genetics
4.
Tissue Antigens ; 66(2): 125-30, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16029432

ABSTRACT

Type 1 diabetes is the consequence of exposure of genetically susceptible individuals to specific environmental precipitants. The innate immune system provides the initial response to exogenous antigen and links with the adaptive immune system. The aim of this study was to assess the role of polymorphisms occurring in the cytoplasmic region of toll-like receptor (TLR) 3 gene and immediate 5' sequence, in subjects of Zulu descent with type 1 diabetes in KwaZulu-Natal, South Africa. Seventy-nine subjects with type 1 diabetes and 74 healthy normal glucose tolerant gender-matched control subjects were studied. Parts of exon 4 and exon 3/intron 3 of the TLR3 gene were studied by polymerase chain reaction, direct sequencing and restriction enzyme digestion with Bts 1. Of the nine polymorphisms studied, a significant association with type 1 diabetes was found for the major allele in the 2593 C/T polymorphism and for the minor alleles in the 2642 C/A and 2690 A/G polymorphisms, which were found to be in complete linkage disequilibrium. Correction of the P-values for the number of alleles studied, however, rendered the results no longer significant. These results suggest that polymorphisms in the TLR3 gene, which is part of the innate immune system, may be associated with type 1 diabetes in this population.


Subject(s)
Black People/genetics , Diabetes Mellitus, Type 1/genetics , Membrane Glycoproteins/genetics , Polymorphism, Genetic , Receptors, Cell Surface/genetics , Adult , Alleles , Case-Control Studies , Diabetes Mellitus, Type 1/ethnology , Exons , Female , Gene Frequency , Genetic Predisposition to Disease , Humans , Introns , Male , South Africa , Toll-Like Receptor 3 , Toll-Like Receptors
5.
BJOG ; 111(9): 1012-3, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15327619

ABSTRACT

The possible role of the beta-subunit of the epithelial sodium channel T594M polymorphism in hypertensive disorders of pregnancy has not been examined. This study compared Black South African women with pre-eclampsia (n= 204), early onset pre-eclampsia (n= 67), eclampsia (n= 120) and gestational hypertension (n= 78) with 338 women from the same ethnic group who had full-term normotensive pregnancies, for the presence of the T594M polymorphism. The variant allele was detected in 1.7% to 3.8% of the various patient groups and in 3.6% of the control group reflecting no significant difference. These results suggest that the T594M polymorphism in the sodium channel beta-subunit is not associated with the pathogenesis of pre-eclampsia or gestational hypertension.


Subject(s)
Black People/genetics , Eclampsia/genetics , Mutation/genetics , Protein Subunits/genetics , Sodium Channels/genetics , Female , Humans , Nerve Tissue Proteins , Polymorphism, Genetic/genetics , Pre-Eclampsia/genetics , Pregnancy , South Africa , Voltage-Gated Sodium Channel beta-2 Subunit
6.
Cardiovasc J S Afr ; 15(3): 111-7, 2004.
Article in English | MEDLINE | ID: mdl-15258620

ABSTRACT

The lipoprotein(a) [Lp(a)] and apolipoprotein E (apoE) polymorphisms have been shown to be important genetic determinants of cardiovascular risk. Their effect on coronary heart disease (CHD) is less clear, particularly in Asian Indians who are at high risk for this disease. The aim of this study was to examine the association of the Lp(a) promoter pentanucleotide repeat polymorphism and the apoE codon 112 and 158 genotypes in 195 young South African Indian patients (< or = 45 years) with myocardial infarction (MI). Results were compared with 300 healthy age-matched control subjects drawn from the same community and 107 unaffected siblings (18-45 years). In addition, fasting lipograms were performed on all patients and a detailed history of conventional risk factors and family background was obtained. Of the six different Lp(a) alleles detected, the 8-repeat sequence was most frequently seen. However, no difference in frequencies existed between patient and control groups. The most frequently occurring apoE genotype in the three study groups was E3/E3 (patients 71%; siblings 70%; controls 70%). A significant difference in the E3/E4 genotype was seen between patients and controls (23% vs 14%; p = 0.018) and between siblings and controls (24% vs 14%; p = 0.027). These patients were also more likely to have significantly higher low-density lipoprotein (LDL) and lower high-density lipoprotein (HDL) levels (p = 0.005 and 0.045, respectively). No association was observed between any of the Lp(a) or apoE genotypes and conventional risk factors such as smoking, diabetes, hypertension, obesity or a family history of CHD. In conclusion, the apoE3/E4 genotype is strongly associated with the incidence of myocardial infarction in young South African Indians. This genotype also adversely affects LDL and HDL cholesterol levels, both of which contribute to premature atherosclerosis. In contrast, the Lp(a) pentanucleotide repeat polymorphism does not appear to have any aetiological role in MI in this population.


Subject(s)
Apolipoproteins E/genetics , Lipoprotein(a)/genetics , Myocardial Infarction/blood , Apolipoprotein E3 , Apolipoprotein E4 , Apolipoproteins E/blood , Case-Control Studies , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Genotype , Humans , Incidence , India/ethnology , Lipoprotein(a)/blood , Middle Aged , Myocardial Infarction/epidemiology , Myocardial Infarction/genetics , Polymorphism, Genetic , Risk Factors , South Africa/epidemiology
7.
Cardiovasc J S Afr ; 15(1): 22-6, 2004.
Article in English | MEDLINE | ID: mdl-14997233

ABSTRACT

The renin-angiotensin system plays an important role in cardiovascular regulation. Abnormalities in genetic components of this system, such as the angiotensin-converting enzyme (ACE) gene, angiotensin II type 1 (AT1) receptor gene and angiotensinogen (AGT) gene, may cause a variety of adverse cardiovascular effects. It was the aim of this study, therefore, to investigate the involvement of the ACE insertion/deletion (I/D), AT1 receptor 1166 A->C and AGT M235T polymorphisms as predisposing factors for myocardial infarction (MI) in 195 young South African Indians (C AT1 receptor polymorphism with respect to both genotype and allelotype (p > 0.70), or in the genotype or allele frequency distribution of the AGT M235T polymorphism (p > 0.44). However, a significant in crease was noted for both the AT1 receptor C variant (p = 0.025) and the AGT T variant (p = 0.047) in hypertensive patients compared with those who were normotensive. In conclusion, results of this study indicate that the ACE I/D, the 1166 A->C AT1 receptor and AGT M235T polymorphisms do not confer any increased risk for MI in young South African Indians.


Subject(s)
Myocardial Infarction/genetics , Polymorphism, Genetic/genetics , Renin-Angiotensin System/genetics , Adolescent , Adult , Alleles , Angiotensinogen/genetics , Family Health , Gene Deletion , Genetic Markers/genetics , Genetic Predisposition to Disease/genetics , Humans , India/ethnology , Middle Aged , Peptidyl-Dipeptidase A/genetics , Receptor, Angiotensin, Type 1/genetics , South Africa/ethnology , Statistics as Topic
8.
Int J Gynecol Cancer ; 13(4): 444-9, 2003.
Article in English | MEDLINE | ID: mdl-12911720

ABSTRACT

Mutations in the BRCA and p53 tumor suppressor genes are implicated in the oncogenesis of ovarian tumors although their exact roles remain unclear. Despite recognized ethnic differences in the frequency of ovarian cancer and in genetic polymorphisms between populations, studies carried out so far have focused almost entirely on Caucasian subjects. In this study, undertaken at King Edward VIII Hospital, Durban, South Africa, we examined blood and/or primary epithelial ovarian tumor tissue from 75 black South African women for the presence of the three most commonly occurring BRCA 1 and 2 mutations (185delAG, 5382insC and 6174delT). The p53 codon 72 allele status was also examined and results were compared to a reference cohort comprising 340 ethnically matched subjects. None of the BRCA 1 or 2 mutations were detected in the patient group. The codon 72 Arg allele frequency in lymphocytic DNA was not significantly different compared with the control group. In contrast, in ovarian tumor DNA, the Arg allele was found significantly more frequently than in the controls; this was observed in terms of both Arg allele frequency (45% vs. 31%; P = 0.017) and Arg homozygosity (20% vs. 9%; P = 0.039). Tumors with the more aggressive serous papillary cystadenomatous histology had a markedly higher Arg frequency (45%) than the mucinous cystadenomas (25%). The higher frequency of the Arg allele detected in this study in black South Africans with ovarian tumors suggests a possible role in malignant transformation and may constitute a risk factor for ovarian and other epithelial cancers through mechanisms yet to be elucidated.


Subject(s)
Black People/genetics , Carcinoma/genetics , Genes, BRCA1 , Genes, BRCA2 , Genes, p53 , Mutation , Ovarian Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Alleles , Carcinoma/ethnology , Carcinoma/pathology , DNA, Neoplasm , Female , Genes, Tumor Suppressor , Genetic Markers/genetics , Genetic Predisposition to Disease , Humans , Middle Aged , Ovarian Neoplasms/ethnology , Ovarian Neoplasms/pathology , Polymerase Chain Reaction , Polymorphism, Genetic , Prognosis , Sampling Studies , Sensitivity and Specificity
9.
Cardiovasc J S Afr ; 14(3): 127-32, 2003.
Article in English | MEDLINE | ID: mdl-12844196

ABSTRACT

Although coronary heart disease (CHD) is extremely common in South African Indians, there is little published data on the possible causes leading to myocardial infarction (MI) in young Indians. The aim of this study was to identify common environmental risk factors and to examine the relationship between two polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene, the 677 C right arrow-hooked T and 1298 A right arrow-hooked C in young South African Indians with MI. Demographic and risk factor data were obtained from245 patients

Subject(s)
Genetic Predisposition to Disease , Methylenetetrahydrofolate Dehydrogenase (NADP)/genetics , Myocardial Infarction/ethnology , Myocardial Infarction/genetics , Polymorphism, Genetic , Adult , Age Factors , Base Sequence , Chi-Square Distribution , Cohort Studies , Female , Humans , Hyperlipidemias/complications , Incidence , India/ethnology , Male , Methylenetetrahydrofolate Dehydrogenase (NADP)/blood , Middle Aged , Molecular Sequence Data , Obesity/complications , Polymerase Chain Reaction , Probability , Risk Factors , Sampling Studies , South Africa/epidemiology , Statistics, Nonparametric
10.
BJOG ; 110(3): 327-8, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12628278

ABSTRACT

It has been suggested that gene aberrations may contribute to vascular endothelial dysfunction of pre-eclampsia in Caucasian and Japanese women. This study was undertaken to examine the association between pre-eclampsia in Black Zulu speaking South African women and the Factor 5 Leiden mutation. 100 patients with pre-eclampsia comprised the study group. The control group comprised 110 normotensive pregnant women of the same population group. Genotyping was performed to detect the G or A allele at residue 506 of the Factor V gene, and the C or T allele at residue 455 of the thrombomodulin gene. Our findings demonstrate that these particularly genetic loci are of little use in disease association studies for pre-eclampsia in homogenous Zulu speaking Africans.


Subject(s)
Black People/genetics , Eclampsia/genetics , Factor V Deficiency/genetics , Factor V/genetics , Prothrombin/genetics , Thrombomodulin/genetics , Adolescent , Adult , Base Pair Mismatch/genetics , Female , Gene Rearrangement/genetics , Genotype , Humans , Mutation/genetics , Polymerase Chain Reaction/methods , Pre-Eclampsia/genetics , Pregnancy , South Africa/ethnology
11.
Int J Gynecol Cancer ; 12(4): 383-8, 2002.
Article in English | MEDLINE | ID: mdl-12144687

ABSTRACT

The usefulness of the arginine (Arg) residue at codon 72 of the p53 tumor suppressor gene as a marker for the risk of cervical cancer remains unclear. Studies to date have focused mainly on Caucasian subjects despite marked ethnic variations in both the p53 polymorphism and the frequency of cervical carcinoma. Furthermore, not all studies have taken into account the type of human papillomavirus (HPV) infection present. In this study, undertaken at King Edward VIII Hospital, Durban, South Africa, we determined the p53 codon 72 status in 281 black South African women with cervical cancer and 340 ethnically matched healthy control subjects. In addition, HPV DNA was confirmed in 190 cervical tumors and the viral type determined. Results showed that overall more cancer patients than control subjects had an Arg allele at codon 72 with respect to both genotype and allelotype (P < 0.05). A significantly higher (P < 0.001) Arg allele frequency (55%) was also observed in patients whose tumors contained low or intermediate risk HPV DNA compared with control subjects (31%); the Arg homozygosity rate was 34% and 9% in patients and controls, respectively (P < 0.001). In contrast, patients harboring HPV 16/18 infections showed no differences in p53 status compared with controls. It would appear that, in the absence of HPV 16/18 infections, the Arg allele at codon 72 of the p53 tumor suppressor gene may constitute a risk factor for carcinogenesis of the cervix.


Subject(s)
Genes, p53/genetics , Papillomaviridae/genetics , Papillomavirus Infections/genetics , Tumor Virus Infections/genetics , Uterine Cervical Neoplasms/virology , Black People/genetics , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/virology , Case-Control Studies , Codon , DNA Primers , DNA, Viral/genetics , Female , Humans , Papillomaviridae/classification , Papillomaviridae/isolation & purification , Polymerase Chain Reaction , Polymorphism, Genetic , Risk Factors , South Africa , Uterine Cervical Neoplasms/genetics
12.
BJOG ; 109(5): 574-5, 2002 May.
Article in English | MEDLINE | ID: mdl-12066950

ABSTRACT

This pilot study examined Factor V Leiden (R506Q), prothrombin (20210G-->A), thrombomodulin (A455V) and MTHFR (677C-->T) in 100 Zulu-speaking black South African women with placental abruption and 217 controls. The Factor V Leiden and prothrombin variant gene alleles were not detected in either patient or control groups. The thrombomodulin polymorphic variant was not seen in the patient group but three heterozygotes (1%) were found in the controls. No homozygotes for the MTHFR T677 variant were detected in the patients but two (1%) were noted in the controls; the normal and heterozygote genotype and allele frequencies for this polymorphism were similar in the two groups.


Subject(s)
Abruptio Placentae/genetics , Polymorphism, Genetic/genetics , Abruptio Placentae/ethnology , Black People/genetics , Factor V/genetics , Female , Heterozygote , Humans , Pilot Projects , Pregnancy , Prothrombin/genetics , South Africa/ethnology , Thrombomodulin/genetics
13.
East Afr Med J ; 78(11): 604-7, 2001 Nov.
Article in English | MEDLINE | ID: mdl-12219967

ABSTRACT

OBJECTIVE: To determine whether polymorphic differences exist between black, white and Indian South Africans in genes associated with bone mineral density and osteoporosis. DESIGN: Genes selected were the vitamin D receptor (Apa I and Taq I polymorphisms) and collagen (Sp I transcription factor polymorphism) using standard molecular biology techniques. SETTING: Department of Chemical Pathology, Nelson R Mandela School of Medicine, University of Natal, Durban, South Africa. SUBJECTS: Healthy male and female blood donors living in the Durban metropolitan region, South Africa. The group comprised black Africans (n=264), white Caucasians (n=247) and Asians of Indian origin (n=194). RESULTS: No significant differences in genotypes were seen between white and Indian subjects. Blacks had a significantly higher frequency of the TT Taq I genotype and a significantly lower frequency of the Ss Sp I genotype. No ss genotype was detected in blacks. CONCLUSION: The very low frequency of the collagen Sp I s allele and higher frequency of the VDR T allele in blacks may be associated with the lower incidence of osteoporosis in this ethnic group.


Subject(s)
Black People/genetics , Collagen Type I/genetics , Osteoporosis/genetics , Polymorphism, Genetic , Receptors, Calcitriol/genetics , White People/genetics , Female , Genotype , Humans , India/ethnology , Male , South Africa
14.
Hypertens Pregnancy ; 19(3): 309-14, 2000.
Article in English | MEDLINE | ID: mdl-11118404

ABSTRACT

OBJECTIVES: Apolipoprotein E may contribute to the hypertiglyceridemia and consequent endothelial dysfunction of preeclampsia. We carried out a study to determine whether the apolipoprotein E genotype plays any role as a risk factor for preeclampsia in a black South African population with a high incidence of preeclampsia. DESIGN: A descriptive, prospective study design was used. SETTING: King Edward VIII Hospital, a tertiary care, referral academic hospital in Durban, South Africa. PATIENTS AND PARTICIPANTS: One hundred three South African Zulu women with preeclampsia and 110 healthy normotensive women attending the antenatal clinic were recruited. MAIN OUTCOME MEASURES: The relationship between the apolipoprotein E allele and genotype frequencies to preeclampsia as well as adverse perinatal outcome. RESULTS: The frequencies of varepsilon2 and varepsilon4 alleles (0. 19 and 0.25, respectively) were much higher than those reported in other population groups. However, there was no significant difference in the apolipoprotein E genotype and allele frequencies between the study and the control groups. The varepsilon2/2 genotype was associated with increased risk of perinatal death (p = 0.047). CONCLUSION: The study suggests that, despite the high incidence of both preeclampsia and the varepsilon2 and varepsilon4 alleles in South African Zulu women, apolipoprotein E genotype does not appear to be a risk factor for preeclampsia in this population.


Subject(s)
Apolipoproteins E/genetics , Black People/genetics , Gene Frequency/genetics , Hypertriglyceridemia/genetics , Polymorphism, Genetic/genetics , Pre-Eclampsia/genetics , Adolescent , Adult , Alleles , Case-Control Studies , Female , Genotype , Humans , Hypertriglyceridemia/blood , Hypertriglyceridemia/epidemiology , Incidence , Infant Mortality , Infant, Newborn , Pre-Eclampsia/blood , Pre-Eclampsia/epidemiology , Pregnancy , Prospective Studies , Risk Factors , South Africa/epidemiology , Urban Population
15.
BJOG ; 107(9): 1164-5, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11002963

ABSTRACT

The p53 codon 72 genotype was examined in blood samples taken from 121 Zulu-speaking black South African women with histologically proven squamous carcinoma of the cervix. Freshly biopsied tumour tissue was also available for human papillomavirus subtyping from 100 of these women. A control group consisted of 251 healthy race-matched women attending a contraceptive service facility. The results show that there were no statistically significant differences in the frequency of the homozygous arginine genotype between patients with cancer of cervix, irrespective of human papillomavirus status, and healthy controls. This finding suggests that the arginine allele does not predispose towards viral tumour genesis in this population, and supports the findings of research done in other ethnic groups.


Subject(s)
Carcinoma, Squamous Cell/genetics , Genes, p53/genetics , Polymorphism, Genetic/genetics , Uterine Cervical Neoplasms/genetics , Alleles , Arginine/blood , Carcinoma, Squamous Cell/blood , Carcinoma, Squamous Cell/virology , Female , Humans , Papillomaviridae/isolation & purification , Proline/blood , Risk Factors , South Africa/ethnology , Uterine Cervical Neoplasms/blood , Uterine Cervical Neoplasms/virology
16.
Br J Obstet Gynaecol ; 106(11): 1219-20, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10549971

ABSTRACT

The polymorphic C677T mutation in the gene encoding 5,10 methylenetetrahydrofolate reductase has been shown to be a risk factor for pre-eclampsia in Japanese and European women when inherited as a homozygous trait. We attempted to verify these findings in a black African population with a high incidence of pre-eclampsia. No difference in frequency of the T-allele was observed in 105 women with pre-eclampsia, compared with 110 healthy pregnant normotensive women. Only one woman with pre-eclampsia was TT homozygous, suggesting that methylenetetrahydrofolate reductase polymorphism is not an important factor in the pathogenesis of pre-eclampsia in black South African women.


PIP: This study aims to determine whether the C677T 5,10 methylenetetrahydrofolate reductase (MTHFR) polymorphism plays any role as a risk factor for preeclampsia in black South African women. A total of 105 pregnant women with preeclampsia were included in the study and were subjected to several tests. Test results showed that the MTHFR genotypes and allele frequencies in the study group and control group have no significant difference in the frequencies of the homozygous TT genotype or the T-allele. Among the respondents, only one woman with preeclampsia was homozygous for the C677T mutation. Findings indicate that preeclampsia in black South African women affects 18% of pregnancies. In addition, the C677T mutation cannot be considered an important factor in the pathogenesis of preeclampsia in this study population. Further studies are required for clarifications concerning these issues.


Subject(s)
Oxidoreductases Acting on CH-NH Group Donors/metabolism , Pre-Eclampsia/enzymology , Adolescent , Adult , Female , Gene Frequency , Genotype , Humans , Methylenetetrahydrofolate Reductase (NADPH2) , Oxidoreductases Acting on CH-NH Group Donors/genetics , Polymorphism, Genetic , Pregnancy , South Africa
17.
J Lipid Res ; 39(5): 1046-54, 1998 May.
Article in English | MEDLINE | ID: mdl-9610772

ABSTRACT

Phytosterolemia is an autosomal recessive disorder characterized by the excessive absorption, reduced excretion, and consequent high tissue and plasma levels of plant sterols, by the presence of tendon xanthomas, and by premature atherosclerosis. Low HMG-CoA reductase (HRase) activity and mass have been reported in liver and mononuclear leucocytes and low mRNA levels in liver from phytosterolemic subjects. These results led to the proposal that the primary defect in this condition involves the HRase gene locus. We examined this hypothesis in phytosterolemic subjects and heterozygous parents from four unrelated families. A variable number tandem repeat (VNTR) polymorphism of the HRase gene in the three informative families and a ScrFI restriction fragment length polymorphism (RFLP) within intron 2 of the gene in one of these families, segregated independently of the disease phenotype. Biological parentage was confirmed in the family in whom both polymorphisms failed to segregate with the disorder. These results conclusively exclude the HRase gene locus as the site of the primary defect in phytosterolemia. The study was extended by examining plasma levels of mevalonic acid and lathosterol, both markers of cholesterol biosynthesis, in response to cholestyramine, a bile acid sequestrant that is known to up-regulate HRase. Oral administration of cholestyramine resulted in a substantial (7.7-fold) increase in mevaIonic acid levels in two phytosterolemic subjects, compared with a 2.2-fold rise in their obligate heterozygote parents and a 2.3-fold increase in three healthy control subjects. The lathosterol/cholesterol (L/C) ratio showed a quantitatively similar response. Baseline levels of mevalonate and the L/C ratio were low in the phytosterolemic patients in conformity with reports of reduced cholesterol biosynthesis and HRase activity in this disorder. These functional data provide support for the concept that the primary defect in phytosterolemia does not affect a trans gene locus responsible for the constitutive expression or regulation of HMG-CoA reductase.


Subject(s)
Hydroxymethylglutaryl CoA Reductases/physiology , Lipid Metabolism, Inborn Errors/enzymology , Phytosterols/blood , Adolescent , Adult , Arteriosclerosis/complications , Arteriosclerosis/enzymology , Arteriosclerosis/genetics , Child , Cholestyramine Resin , Female , Genetic Linkage , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Lipid Metabolism, Inborn Errors/complications , Lipid Metabolism, Inborn Errors/diagnosis , Lipid Metabolism, Inborn Errors/genetics , Male , Middle Aged , Minisatellite Repeats , Pedigree , Polymorphism, Genetic , Xanthomatosis/complications , Xanthomatosis/enzymology , Xanthomatosis/genetics
18.
S Afr Med J ; 88(1): 39-42, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9539934

ABSTRACT

OBJECTIVE: To identify by means of genetic analyses individuals who are at risk of developing medullary thyroid cancer that is a component of multiple endocrine neoplasia. SUBJECTS: A three-generation kindred with clinically and biochemically diagnosed medullary thyroid cancer. METHOD: Identification of a heterozygote mutation by nucleic acid sequencing and restriction analyses. RESULTS: A heterozygote T-->C (Cys-->Arg) mutation at codon 618 in exon 10 of the RET proto-oncogene was identified in 4 family members who had previously been diagnosed with medullary thyroid cancer. The same mutation was also found in one of the proband's presymptomatic children who subsequently underwent a pre-emptive thyroidectomy. The genetic diagnosis was confirmed by histology. No mutations were detected in any other family members. CONCLUSION: Identification of heterozygote germline mutations in multiple endocrine neoplasia is direct, highly accurate and cost-effective. This study demonstrates that, appropriately used, molecular diagnosis can supersede conventional biochemical methods in the management of patients with inherited cancers.


Subject(s)
Carcinoma, Medullary/diagnosis , DNA Mutational Analysis , Genetic Testing , Multiple Endocrine Neoplasia Type 2a/diagnosis , Adult , Calcitonin/blood , Carcinoma, Medullary/genetics , Child , Child, Preschool , Female , Germ-Line Mutation , Humans , Hyperparathyroidism/diagnosis , Hyperparathyroidism/genetics , Multiple Endocrine Neoplasia Type 2a/genetics , Pedigree , Pentagastrin , Proto-Oncogene Mas , Sequence Analysis, DNA
19.
Diagn Mol Pathol ; 5(3): 181-6, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8866231

ABSTRACT

We examined 232 breast carcinomas for c-erbB-2 amplification by Southern analysis using two different cDNA probes. Using these same probes, 95 of these tumors were also examined for mRNA expression by Northern analysis. Amplification was detected in 20 and 17% of the tumors with the probes pHER 2 and pCER 204, respectively, but only 10% showed amplification with both probes. A significantly higher incidence (p < 0.01) of mRNA overexpression was detected with the pHER 2 probe (34%) compared with the pCER 204 probe (16%), with only 11% of tumors demonstrating overexpression with both probes. A total of 10 tumors (11%) exhibited amplification as well as overexpression with pHER 2, whereas significantly fewer (3%) manifested both abnormalities with the larger pCER 204 probe (p < 0.05). Amplification of c-erbB-2, as detected with the pHER 2 probe but not with the pCER 204 probe, was significantly associated with the absence of both estrogen and progesterone receptors (p < 0.05 and p < 0.01, respectively). No relationship was found with other clinical prognostic indicators, such as nodal involvement and metastases. As determined by either probe, overexpression was not associated with prognostic indicators. There was no significant difference in the c-erbB-2 status of tumors from different racial groups.


Subject(s)
Breast Neoplasms/genetics , Carcinoma/genetics , DNA Probes/analysis , DNA, Complementary/analysis , DNA, Neoplasm/analysis , Genes, erbB-2/genetics , DNA Probes/genetics , Female , Gene Amplification/genetics , Humans , Proto-Oncogene Mas , Receptor, ErbB-2/biosynthesis , Reproducibility of Results
20.
Am J Med Qual ; 11(1): 18-24, 1996.
Article in English | MEDLINE | ID: mdl-8763217

ABSTRACT

An attempt was made to formulate a tool that, when compared to the appropriateness evaluation protocol (AEP) used for evaluating the utilization of hospital services for medical patients, would be an improvement. To establish this, a four-phase project was evolved, which included: (a) taxonomy definition of medical and nonmedical reasons for acute-care hospital bed utilization for a day of care, (b) use of the preliminary protocol by trained nurses to extend the range of clinical conditions included, (c) independent review of the protocol by three senior physicians, and (d) comparative interrater reliability and feasibility study between the new instrument-the medical patients assessment protocol (MPAP) and the AEP. We found the MPAP to have a higher inter-rater reliability than the AEP (kappa = 0.94 and 0.78, respectively), to be more clinically oriented, more comprehensive, and similar to the AEP regarding the time required for investigation of cases. Therefore, we recommend the use of the MPAP for management and quality control of medical hospitalized patients.


Subject(s)
Case Management/organization & administration , Hospitals/statistics & numerical data , Utilization Review/methods , Female , Humans , Israel , Length of Stay , Male , Middle Aged , Observer Variation , Reproducibility of Results , Severity of Illness Index
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