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Qiong Yang

Publications and source records attributed to Qiong Yang.

33 records · Page 2Linked to original sources
PubMed2005

Genome-wide linkage analysis to age at natural menopause in a community-based sample: the Framingham Heart Study.

OBJECTIVE: To identify chromosomal regions linked to age at natural menopause. DESIGN: Two-generation families studied with a 10-centimorgan (cM) genome-wide scan. SETTING: The Framingham Study, a community-based epidemiologic study. PATIENT(S): A total of 861 women in 291 families reporting a natural menopause (mean age at menopause, 49 years). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Multipoint variance components linkage analysis was performed with Genehunter software (Whitehead Institute, Massachusetts Institute of Technology, Boston, MA) for age at natural menopause. RESULT(S): In the crude variance components analysis, 11 chromosomes had a log odds ratio (LOD) score of > or =1.0. Two chromosomal regions revealed suggestive linkage: chromosome 8 at 26 cM (LOD 2.6; nearest marker GATA23D06) and chromosome 16 at 11 cM (LOD 2.4; nearest marker ATA41E04). In the analysis adjusted for generation, smoking, and body mass index, chromosome 11 revealed suggestive linkage at 113 cM (LOD 2.1; nearest marker GATA23E06). CONCLUSION(S): We have identified novel loci suggestive for linkage to age at natural menopause. Further research is needed to identify genes involved in the onset of menopause, which might provide insights into loss of fertility.

Adult↗
PubMed2005

Genome-wide search for genes affecting serum uric acid levels: the Framingham Heart Study.

Serum uric acid levels are associated with hypertension, cardiovascular disease, and renal disease. Uric acid has been shown to be heritable; however, genome-wide linkage analyses have not been reported. Genome-wide multipoint variance components linkage analyses with 401 markers spaced at approximately 10 centimorgan (cM) were conducted on 1258 subjects of the Framingham Heart Study, using the average of two serum uric acid measurements obtained in examinations 1 and 2 around 1971 and 1979. Covariates in fully adjusted model included sex, age, body mass index (BMI), serum creatinine, alcohol consumption, diabetes, diuretic treatment, and triglycerides. To investigate possible pleiotropic effects between uric acid and covariates that may have a genetic component, bivariate linkage analyses of uric acid with BMI, triglycerides, and glucose were conducted at the uric acid linkage regions. The heritability of uric acid was 0.63. The highest multipoint log-of-the-odds (LOD) score was 3.3 at 50 cM on chromosome 15 for age-sex-adjusted uric acid, but decreased to 1.5 after multivariable adjustment. Additional evidence of linkage was seen on chromosomes 2 (LOD score 1.1 at 4 cM) and 8 (LOD score 1.7 at 6 cM) for multivariable-adjusted uric acid. Pleiotropic effects were only found between uric acid and glucose and BMI at chromosomes 8 and 15 linkage locations, respectively. We have identified several novel loci linked to uric acid. We found possible pleiotropic effects between uric acid and BMI and glucose. Further research is necessary to identify the genes involved in uric acid metabolism and their roles in hypertension, cardiovascular disease, and renal disease.

Adult↗
PubMed2005

Genome-wide linkage analysis to urinary microalbuminuria in a community-based sample: the Framingham Heart Study.

INTRODUCTION: Microalbuminuria is a powerful risk factor for cardiovascular disease. It is not known whether genetic factors play a role in the expression of microalbuminuria in population-based samples. METHODS: Genome-wide variance components linkage-analysis using 401 markers spaced at approximately 10 cM was performed on subjects from 330 extended families of the Framingham Heart Study; a subanalysis was performed on families enriched for hypertension. Urinary microalbumin was indexed to urinary creatinine [urine albumin/creatinine ratio (UACR)] and was log-transformed for analysis. Residuals of log-transformed UACR adjusted for age, gender, body mass index, diabetes, systolic blood pressure, hypertension treatment, smoking, and serum creatinine were used in the linkage analysis. RESULTS: Among 1055 subjects (52% women), mean age 56 years, median UACR was 5.8 mg/g (11% >30 mg/g). The unadjusted heritability for UACR was 0.20; after multivariable adjustment, heritability was 0.16. The peak multivariable-adjusted multipoint logarithm of odds (LOD) score was 2.22 on chromosome 8 at 135 cM (marker D8S1179); one LOD support interval = 129 - 145 cM. In the subanalysis in families enriched for hypertension (N= 676), the peak multivariable-adjusted LOD score of 2.11 was observed at the same location. CONCLUSION: We found suggestive linkage to urinary microalbumin on chromosome 8. At least one potential candidate gene implicated in the pathogenesis of nephropathy (HAS2) lies in this region. Further research is warranted to understand the genetic basis of microalbuminuria.

Adult↗
PubMed2004

Prophylactic vaccination with phage-displayed epitope of C. albicans elicits protective immune responses against systemic candidiasis in C57BL/6 mice.

Epitope LKVIRK on 47 kDa of heat shock protein (Hsp) 90 of Candida albicans, corresponding to residues 386-391 of the Hsp90, is recognized by patients recovering from invasive candidiasis. The efficacy of hybrid phage displaying epitope LKVIRK in the N-terminal region of the major coat protein (pVIII) in inducing anti-invasive candidiasis immune response was studied in C57BL/6 mice. Indirect phage-ELISA results demonstrated that the mice immunized with hybrid phage had significantly higher titers of epitope LKVIRK-specific serum IgG as compared to those immunized with heat-killed C. albicans (HK-CA). C57BL/6 mice immunized either with hybrid phage or with wild-type phage also developed significant levels of delayed-type hypersensitivity (DTH) response and splenocyte proliferation, as well as with HK-CA. In addition, high levels of IFN-gamma in the CD4(+) splenocytes from phage-immunized mice were detected as well during 1 week post-inoculation. Furthermore, mice immunized with hybrid phage acquired a resistance to systemic C. albicans infection as confirmed by fewer C. albicans cells in the kidneys, and had a longer lifespan compared to control groups following intravenous challenge with C. albicans. These results indicate that hybrid phage displaying epitope LKVIRK may serve as a potential vaccine conferring a resistance to systemic candidiasis.

Animals↗
PubMed2004

Quantitative DNA fingerprinting may distinguish new primary breast cancer from disease recurrence.

PURPOSE: Approximately 10% of women with breast cancer develop a second breast tumor, either a new primary or a recurrence. Differentiating between these entities using standard clinical and pathologic criteria remains challenging. Ambiguous cases arise, and misclassifications may occur. We investigated whether quantitative DNA fingerprinting, based on allele imbalance (AI) or loss of heterozygosity (LOH), could evaluate clonality and distinguish second primary breast cancer from recurrence. METHODS: We developed a scoring system based on the AI/LOH fingerprints of 20 independent breast tumors and generated a decision rule to classify any breast tumor pair as related or unrelated. We validated this approach on eight related tumors (cancers and synchronous positive lymph nodes). Finally, we analyzed paired tumors from 13 women (bilateral cancers, primary tumors and contralateral positive axillary lymph nodes, or two ipsilateral tumors). Each pair's genetic classification was compared with their clinical diagnosis and outcome. RESULTS: Each independent cancer had a unique fingerprint. Every tumor pair's relationship was quantifiable. Six of eight related tumor pairs were genetically classified correctly, two were indeterminate, and none were misclassified. Among the 13 women with two cancers, four of five clinically indeterminate pairs could be classified genetically. In three of 13 women, the pair's classification contradicted the clinical diagnosis. These women had bilateral cancers genetically classified as related and disease progression. This challenges the paradigm that bilateral cancers represent independent tumors. Overall, women with tumors genetically classified as related had poorer outcomes. CONCLUSION: Quantitative AI/LOH fingerprinting is a potentially valuable tool to improve diagnosis and optimize treatment for the growing number of second breast malignancies.

Alleles↗
PubMed2004

Evidence for a modifier of onset age in Huntington disease linked to the HD gene in 4p16.

Huntington disease (HD) is a neurodegenerative disorder caused by the abnormal expansion of CAG repeats in the HD gene on chromosome 4p16.3. A recent genome scan for genetic modifiers of age at onset of motor symptoms (AO) in HD suggests that one modifier may reside in the region close to the HD gene itself. We used data from 535 HD participants of the New England Huntington cohort and the HD MAPS cohort to assess whether AO was influenced by any of the three markers in the 4p16 region: MSX1 (Drosophila homeo box homologue 1, formerly known as homeo box 7, HOX7), Delta2642 (within the HD coding sequence), and BJ56 ( D4S127). Suggestive evidence for an association was seen between MSX1 alleles and AO, after adjustment for normal CAG repeat, expanded repeat, and their product term (model P value 0.079). Of the variance of AO that was not accounted for by HD and normal CAG repeats, 0.8% could be attributed to the MSX1 genotype. Individuals with MSX1 genotype 3/3 tended to have younger AO. No association was found between Delta2642 (P=0.44) and BJ56 (P=0.73) and AO. This study supports previous studies suggesting that there may be a significant genetic modifier for AO in HD in the 4p16 region. Furthermore, the modifier may be present on both HD and normal chromosomes bearing the 3 allele of the MSX1 marker.

Adolescent↗
PubMed2004

Genomewide linkage analysis to serum creatinine, GFR, and creatinine clearance in a community-based population: the Framingham Heart Study.

Kidney disease is a risk factor for the development of cardiovascular disease, all-cause mortality, and ESRD. It is not known to what extent genetic factors play a role in the development of kidney disease in the general population. Multipoint variance components linkage analysis was performed using Genehunter on 330 families from the Framingham Heart Study offspring cohort, using a 10-cM genomewide scan for serum creatinine, GFR, and creatinine clearance (CRCL) measured from 1998 to 2001. GFR was estimated using the simplified Modification of Diet in Renal Disease Study equation, and CRCL was estimated using the Cockcroft-Gault equation. Covariates in the adjustment included age, gender, body mass index, diabetes, systolic BP, hypertension treatment, tobacco use, and HDL cholesterol. Overall, 1224 subjects (52% women), mean age 59, were available for analysis. Mean creatinine was 0.87 mg/dl, mean GFR was 87 ml/min per 1.73 m(2), and mean creatinine clearance was 100 ml/min. The multivariable-adjusted heritability estimates for creatinine, GFR, and CRCL were 0.29, 0.33, and 0.46, respectively. The peak log of the odds ratio (LOD) scores for serum creatinine, GFR, and CRCL were 2.28 at 176 cM on chromosome 4, 2.19 at 78 cM on chromosome 4, and 1.91 at 103 cM on chromosome 3, respectively. In a community-based sample, measures of serum creatinine, GFR, and CRCL are heritable, suggesting an underlying genetic component. These results also provide suggestive evidence for linkage to measures of kidney function. Further research is necessary to identify the genes involved in the development of kidney disease and to understand their roles in this complex process.

Adult↗
PubMed2004

[Characterization of injured child psychology-a case-control study].

OBJECTIVE: To study psychologic features of accidentally injured children to provide basis for application of psychologic intervening measures. METHODS: Eysenck personality questionnaire (EPQ) and Achenback child behavior capacity list (CBCL) (list for parents) were used to test accidentally injured children 7 - 11 years of age who were hospitalized (injury group) and healthy children (control group). Each group was composed of 81 cases. RESULTS: (1) Scores of P, E and N branch capacity lists in EPQ of injury group were all higher than those of control group (P < 0.05 or < 0.001). But the score of L branch capacity of control group was higher than that of injury group (P < 0.001). (2) Boys of injury group in seven factors of restlessness, violation of discipline, attack, harmful contact, schizoid anxiety, depression and body complaint and girls of injury group in seven factors of restlessness, cruelty, attack, depression, body complaint, social flinching and violation of discipline had higher scores than those in control group did (P < 0.01). (3) Detectable rate of behavior problems of injury group was 32.09% (26/81), higher than that of control group [11.11% (9/81), P < 0.001]. The odds ratio (OR) was 3.78, 95% CI was 1.66 approximately 8.59 (P < 0.01). The behavior factor had a lower sensitivity (32.1%) and a higher specificity (88.9%) and lower positive result value (74.3%). (4) Average CBCL score of boys in injury group (39.84 +/- 10.99) was higher than that of girl in injury group (34.26 +/- 10.43, P < 0.05). Boys in two factors of violation of discipline and attack, girls in factor of depression factor M had higher score than the opposite sex subjects did (P < 0.05 or 0.01). (5) Average CBCL score (37.62 +/- 11.03) of injury group was higher than that of control group (17.77 +/- 12.12, P < 0.001). Logistic multiple factor analysis showed that boys' accidentally injured factors were attack, restlessness, violation of discipline, and girls' accidentally injured factors were attack, violation of discipline and depression. CONCLUSION: Accidentally injured children have more psychologic problems in character and behavior. Psychologic education should be given to reduce incidence of accidental injury to children.

Accident Prevention↗
PubMed2003

Genetic analyses of longitudinal phenotype data: a comparison of univariate methods and a multivariate approach.

BACKGROUND: We explored three approaches to heritability and linkage analyses of longitudinal total cholesterol levels (CHOL) in the Genetic Analysis Workshop 13 simulated data without knowing the answers. The first two were univariate approaches and used 1) baseline measure at exam one or 2) summary measures such as mean and slope from multiple exams. The third method was a multivariate approach that directly models multiple measurements on a subject. A variance components model (SOLAR) was employed in the univariate approaches. A mixed regression model with polynomials was employed in the multivariate approach and implemented in SAS/IML. RESULTS: Using the baseline measure at exam 1, we detected all baseline or slope genes contributing a substantial amount (0.08) of variance (LOD > 3). Compared to the baseline measure, the mean measures yielded slightly higher LOD at the slope genes, and a lower LOD at the baseline genes. The slope measure produced a somewhat lower LOD for the slope gene than did the mean measure. Descriptive information on the pattern of changes in gene effects with age was estimated for three linked loci by the third approach. CONCLUSION: We found simple univariate methods may be effective to detect genes affecting longitudinal phenotypes but may not fully reveal temporal trends in gene effects. The relative efficiency of the univariate methods to detect genes depends heavily on the underlying model. Compared with the univariate approaches, the multivariate approach provided more information on temporal trends in gene effects at the cost of more complicated modelling and more intense computations.

Adult↗
PubMed2003

The human D2 dopamine receptor synergizes with the A2A adenosine receptor to stimulate adenylyl cyclase in PC12 cells.

The adenosine A(2A) receptor and the dopamine D(2) receptor are prototypically coupled to G(s) and G(i)/G(o), respectively. In striatal intermediate spiny neurons, these receptors are colocalized in dendritic spines and act as mutual antagonists. This antagonism has been proposed to occur at the level of the receptors or of receptor-G protein coupling. We tested this model in PC12 cells which endogenously express A(2A) receptors. The human D(2) receptor was introduced into PC12 cells by stable transfection. A(2A)-agonist-mediated inhibition of D(2) agonist binding was absent in PC12 cell membranes but present in HEK293 cells transfected as a control. However, in the resulting PC12 cell lines, the action of the D(2) agonist quinpirole depended on the expression level of the D(2) receptor: at low and high receptor levels, the A(2A)-agonist-induced elevation of cAMP was enhanced and inhibited, respectively. Forskolin-stimulated cAMP formation was invariably inhibited by quinpirole. The effects of quinpirole were abolished by pretreatment with pertussis toxin. A(2A)-receptor-mediated cAMP formation was inhibited by other G(i)/G(o)-coupled receptors that were either endogenously present (P(2y12)-like receptor for ADP) or stably expressed after transfection (A(1) adenosine, metabotropic glutamate receptor-7A). Similarly, voltage activated Ca(2+) channels were inhibited by the endogenous P(2Y) receptor and by the heterologously expressed A(1) receptor but not by the D(2) receptor. These data indicate functional segregation of signaling components. Our observations are thus compatible with the proposed model that D(2) and A(2A) receptors are closely associated, but they highlight the fact that this interaction can also support synergism.

4-(3-Butoxy-4-methoxybenzyl)-2-imidazolidinone↗
PubMed2003

A genome-wide search for genes affecting circulating fibrinogen levels in the Framingham Heart Study.

INTRODUCTION: Circulating levels of fibrinogen are associated with atherosclerosis and predict future coronary heart disease and stroke. Levels of fibrinogen are correlated among family members, suggesting a heritable component. Variants of the beta-fibrinogen gene subunit on 4q28 are associated with fibrinogen levels but explain only a small proportion of the total genetic variability. It remains unknown what role, if any, is played by other genetic variants in the inter-individual variability in levels of fibrinogen in the general population. MATERIALS AND METHODS: We conducted a 10-cM spaced genome-wide scan using 402 original cohort subjects and 1193 offspring subjects from 330 extended families of the Framingham Heart Study. Heritability and linkage analyses were carried out using variance component methods. Regression analyses were performed to adjust for traditional risk factors and HindIII beta-148 genotypes. RESULTS AND DISCUSSIONS: The total heritability was estimated as 0.24. The highest and second highest LOD scores of linkage were found on chromosomes 2 (LOD=1.5 at 243 cM) and 10 (LOD=2.4 at 87 cM) using only offspring subjects in the analysis, and on chromosomes 2 (LOD=2.1 at 242 cM) and 10(LOD=1.4 at 86 cM), 17 (LOD=1.4 at 96 cM) and 20 (LOD=1.4 at 80 cM) using both original cohort and offspring. These results suggest that there may be influential genetic regions on these chromosomes. While no linkage with genome-wide significance was detected, further research to confirm our findings is warranted.

Adult↗
PubMed2003

Power evaluations for family-based tests of association with incomplete parental genotypes.

While a variety of methods have been developed to deal with incomplete parental genotype information in family-based association tests, sampling design issues with incomplete parental genotype data still have not received much attention. In this article, we present simulation studies with four genetic models and various sampling designs and evaluate power in family-based association studies. Efficiency depends heavily on disease prevalence. With rare diseases, sampling affecteds and their parents is preferred, and three sibs will be required to have close power if parents are unavailable. With more common diseases, sampling affecteds and two sibs will generally be more efficient than trios. When parents are unavailable, siblings need not be phenotyped if the disease is rare, but a loss of power will result with common diseases. Finally, for a class of complex traits where other genetic and environmental factors also cause phenotypic correlation among siblings, little loss of efficiency occurs to rare disease, but substantial loss of efficiency occurs to common disease.

Data Interpretation, Statistical↗
PubMed2003

Chemokine receptor mutant CX3CR1-M280 has impaired adhesive function and correlates with protection from cardiovascular disease in humans.

The chemokine receptor CX3CR1 is a proinflammatory leukocyte receptor specific for the chemokine fractalkine (FKN or CX3CL1). In two retrospective studies, CX3CR1 has been implicated in the pathogenesis of atherosclerotic cardiovascular disease (CVD) based on statistical association of a common receptor variant named CX3CR1-M280 with lower prevalence of atherosclerosis, coronary endothelial dysfunction, and acute coronary syndromes. However, the general significance of CX3CR1-M280 and its putative mechanism of action have not previously been defined. Here we show that FKN-dependent cell-cell adhesion under conditions of physiologic shear is severely reduced in cells expressing CX3CR1-M280. This was associated with marked reduction in the kinetics of FKN binding as well as reduced FKN-induced chemotaxis of primary leukocytes from donors homozygous for CX3CR1-M280. We also show that CX3CR1-M280 is independently associated with a lower risk of CVD (adjusted odds ratio, 0.60, P = 0.008) in the Offspring Cohort of the Framingham Heart Study, a long-term prospective study of the risks and natural history of this disease. These data provide mechanism-based and consistent epidemiologic evidence that CX3CR1 may be involved in the pathogenesis of CVD in humans, possibly by supporting leukocyte entry into the coronary artery wall. Moreover, they suggest that CX3CR1-M280 is a genetic risk factor for CVD.

Aged↗