Previous studies have suggested that a locus predisposing to specific reading disability (dyslexia) resides on chromosome 6p23-p21.3. We investigated 79 families having at least two siblings affected with phonological coding dyslexia, the most common form of reading disability (617 people genotyped, 294 affected), and we tested for linkage with the genetic markers reported to be linked to dyslexia in those studies. No evidence for linkage was found by LOD score analysis or affected-sib-pair methods. However, using the affected-pedigree-member (APM) method, we detected significant evidence for linkage and/or association with some markers when we used published allele frequencies with weighting of rarer alleles. APM results were not significant when we used marker allele frequencies estimated from parents. Furthermore, results were not significant with the more robust SIMIBD method using either published or parental marker frequencies. Finally, family-based association analysis using the AFBAC program showed no evidence for association with any marker. We conclude that the APM method should be used only with extreme caution, because it appears to have generated false-positive results. In summary, using a large data set with high power to detect linkage, we were unable to find evidence for linkage or association between phonological coding dyslexia and chromosome 6p markers.
Cites: Am J Hum Genet. 1997 Jan;60(1):27-398981944
Cites: Am J Hum Genet. 1996 Apr;58(4):892-58644756
Aboriginals experience high rates of end-stage renal disease (ESRD) and are less likely to receive a kidney transplant from a living donor. We hypothesized that higher rates of hypertension and diabetes in Aboriginal communities would result in fewer potential living donors coming forward and more exclusions for medical reasons. We performed a retrospective study to examine the frequency of potential donor presentation and the reasons for donor exclusion among Aboriginal and Caucasian wait-listed ESRD patients at our center. Three hundred and eighty-five wait-listed patients were studied, including 174 Aboriginals and 211 Caucasians. Time on the waiting list was similar between groups. A similar proportion of Aboriginals and Caucasians had at least one potential donor (40% vs. 46%), and the rate of donor exclusion for medical reasons was also similar (23% vs. 21%). Potential donors to Aboriginals were more likely to be excluded for non-medical reasons (50% vs. 30%; p
The role of anti-nuclear autoantibody (ANA) specificities in immune complexes (IC) formation has been studied to a limited extent in SLE, and not at all in African SLE patients. We compared ANA in IC from Sudanese and Swedish SLE patients. We included 93 Sudanese and 332 Swedish SLE patients fulfilling the 1982 ACR criteria. IC were captured using C1q-coated beads. ANA specificities were quantified in sera and IC. Results were related to modified SLEDAI. Whereas serum levels of anti-Sm, anti-dsDNA and anti-ribosomal P were higher in Swedish patients, IC levels of most ANA specificities were higher among Sudanese patients. This difference was especially prominent for anti-chromatin antibodies, which remained after adjustment for age, disease duration and treatment. Total levels of C1q-binding IC correlated with levels of specific ANA in IC, with highest correlations for anti-chromatin antibodies among Sudanese patients. Whereas occurrence of anti- SSA/Ro60, anti-histone and anti-U1RNP in both serum and IC associated with high SLEDAI score, anti-dsDNA in IC but not in serum associated with high SLEDAI. ANA, especially antibodies targeting chromatin, accumulate more in IC from Sudanese SLE patients. If the autoantibody fraction forming IC is pathogenically important, this might explain the generally described severe SLE in black populations.
OBJECTIVE: To determine whether women in the National Breast and Cervical Cancer Early Detection Program (NBCCEDP) who had findings on a Papanicolaou (Pap) test of atypical squamous cells of undetermined significance (ASC-US) or low-grade squamous intraepithelial lesions (LSIL) were followed up in accordance with the interim guidelines for management of abnormal cervical cytology. METHODS: For this study period, the guidelines for a Pap result of ASC-US or LSIL specified follow-up by Pap tests repeated every 4 to 6 months for 2 years. If a second report of ASC-US or LSIL was made, the patient was to have colposcopy. We analyzed data from 10,004 women who had a result of ASC-US or LSIL followed by a second ASC-US or LSIL from 1991-2000. RESULTS: As judged by the guidelines, 44% of women who had 2 low-grade abnormalities were followed up appropriately with colposcopy. Among women with 2 ASC-US results, those aged less than 30 years were more likely to receive colposcopy than the other age groups, while women who were aged 60 years and older were more likely to be followed up with a third Pap test. For each of the 4 result groups, American Indian or Alaska Native women had the highest percentages of a third Pap test, whereas Black or African-American women had a higher percentage of no follow-up. CONCLUSION: More than one half of the women studied were not followed up in accordance with the established guidelines for managing abnormal cervical cytology. Factors such as age and race or ethnicity influence whether women with cytologic abnormalities receive appropriate follow-up.
AIMS/HYPOTHESIS: Adiponectin is an adipocytokine with lowered blood levels in obesity and Type 2 diabetes mellitus. We sought to define the specific effects of different alleles of the gene encoding adiponectin. METHODS: We studied the associations of adiponectin gene sequence variations with body fat distribution and insulin indices in 503 White and 276 Black subjects of the HERITAGE Family Study cohort and subjects from a Finnish population. RESULTS: The His111 allele frequency of the Tyr111 His polymorphism in Finnish Type 2 diabetic subjects (n=254) was higher (5.1%) than in control subjects (n=270) (2.6%; P = 0.033). In the HERITAGE cohort, the His111 allele was associated with a lower insulin sensitivity index (P = 0.018) and a higher acute insulin response to glucose (P = 0.0098) in Whites. Other variants showed associations with adiposity and plasma lipid values only in Blacks. Among Blacks, the IVS2+G62T variant was associated with body fat (P = 0.002) and total cholesterol values (P = 0.005), and the Gly15Gly variant with cholesterol (P = 0.009) and triglyceride (P = 0.05) levels. The haplotype derived from these two polymorphisms was associated with total body fat, while the IVS2+G62T and Tyr111His-haplotype was associated with body fat and disposition index. CONCLUSIONS: The carriers of the His111 allele may have a higher risk of developing Type 2 diabetes mellitus. Racial differences were found between Blacks and Whites in body composition and lipids according to ACDC genotypes. Sequence variants in the adiponectin gene appear to be associated with diabetes and diabetes-related phenotypes.
This qualitative, community-based research study explored the influence of gender on community perceptions of HIV/AIDS service needs among African immigrant men and women in Calgary, Canada. A total of 41 key informant participants (24 male, 17 female) from 14 sub-Saharan countries completed individual, semi-structured interviews. Thematic interview analysis results produced four themes directly related to HIV and gender, including different sexual standards for men and women, condom use, infidelity, and the need for dialogue between partners on sex and HIV. Each of these themes was related to a contextual theme of "family breakdown", which resulted from cultural adjustment challenges faced by African immigrants. For men, finding suitable employment was a key issue; for women, isolation was identified as an adjustment factor. The findings suggest that a more holistic conception of HIV prevention may be necessary for programmes to be successful and that HIV/AIDS services should be better integrated with newcomer services.
Effects of age, sex, race, and initial fitness on training responses of maximal O(2) uptake (VO(2 max)) are unclear. Data were available on 435 whites and 198 blacks (287 men and 346 women), aged 17-65 yr, before and after standardized cycle ergometer training. Individual responses varied widely, but VO(2 max) increased significantly for all groups. Responses by men and women and by blacks and whites of all ages varied widely. There was no sex difference for change (Delta) in VO(2 max) (ml. kg(-1). min(-1)); women had lower initial values and greater relative (%) increases. Blacks began with lower values but had similar responses. Older subjects had a lower Delta but a similar percent change. Baseline VO(2 max) correlated nonsignificantly with DeltaVO(2 max) but significantly with percent change. There were high, medium, and low responders in all age groups, both sexes, both races, and all levels of initial fitness. Age, sex, race, and initial fitness have little influence on VO(2 max) response to standardized training in a large heterogeneous sample of sedentary black and white men and women.
The purpose of this study was to investigate age-specific spontaneous fetal loss rates of pregnancies without known chromosomal or structural abnormalities from mid-second trimester onward.
The study consisted of 264,653 women screened between October 1995 and September 2000 with available pregnancy outcomes. Pregnancies associated with fetal chromosomal or structural abnormalities, insulin dependent diabetes mellitus, and multiple pregnancies were excluded. Spontaneous fetal losses at or after 15 weeks of gestation were identified. Women were grouped according to maternal age at expected date of delivery. Spontaneous fetal loss rates in each group were evaluated after adjusting fetal losses associated with amniocentesis and identifiable ethnic groups.
Fetal loss rates increased in both younger and older women. The lowest rate was seen in women at mid-20s. Compared with Caucasian and Asian women, black women had higher fetal loss rate at nearly every age group.
The results of the study provided a baseline age-specific spontaneous fetal loss rate of pregnancies at a specified gestational window.
Among adrenergic receptor subtypes that regulate lipid mobilization, the alpha2-adrenergic receptor is involved in the inhibition of fatty acid mobilization from adipose tissue. A C-1291G polymorphism is located in the alpha2-adrenergic receptor gene (ADRA2A) but no association with body fat accumulation has been reported yet.
Body mass index (BMI), fat mass (FAT), percentage body fat (%FAT), trunk-to-extremity skinfold ratio (TER), sum of eight skinfolds (SF8), and abdominal subcutaneous (ASF), visceral (AVF), and total (ATF) fat areas assessed by CT scan have been measured in adult sedentary white (n = 503) and black (n = 276) subjects participating in the HERITAGE Family Study. Association between the C-1291G polymorphism and each phenotype was tested separately in men and women of each race using ANCOVA with the effects of age as covariate in addition to the effects of BMI for TER and of FAT for AVF, ASF, and ATF.
The allele frequencies of the ADRA2A C-1291G polymorphism differed between races. No association was observed in white subjects, except for a moderate effect of the polymorphism accounting for less than 1% of the variance in AVF and ATF in women. In black subjects, however, the G-1291 allele was found to be associated with an increase of TER in men (3.8% of variance accounted for by the polymorphism), while in black women it was associated with a decrease in TER (2.9%) and in AVF (2.5%).
These results suggest a role for the ADRA2A gene in determining the propensity to store fat in the abdominal area, independently of total body fatness.
The discovery (in 1971) of a nearly complete right ulna from the Shungura Formation of the Omo basin provides the opportunity to abalyze the forelimb structure of the Australopithecus boisei form of early hominid. Results from multivariate morphometric analyses show that this bone is unique in shape among the extant hominoids although it is most similar to Pan and Homo. Despite its long slender shaft and large distal articular surface the bone's overall morphology is quite unlike Pongo.