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1.
Sci Rep ; 10(1): 12681, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728164

RESUMO

We investigated the heritability of educational attainment and how it differed between birth cohorts and cultural-geographic regions. A classical twin design was applied to pooled data from 28 cohorts representing 16 countries and including 193,518 twins with information on educational attainment at 25 years of age or older. Genetic factors explained the major part of individual differences in educational attainment (heritability: a2 = 0.43; 0.41-0.44), but also environmental variation shared by co-twins was substantial (c2 = 0.31; 0.30-0.33). The proportions of educational variation explained by genetic and shared environmental factors did not differ between Europe, North America and Australia, and East Asia. When restricted to twins 30 years or older to confirm finalized education, the heritability was higher in the older cohorts born in 1900-1949 (a2 = 0.44; 0.41-0.46) than in the later cohorts born in 1950-1989 (a2 = 0.38; 0.36-0.40), with a corresponding lower influence of common environmental factors (c2 = 0.31; 0.29-0.33 and c2 = 0.34; 0.32-0.36, respectively). In conclusion, both genetic and environmental factors shared by co-twins have an important influence on individual differences in educational attainment. The effect of genetic factors on educational attainment has decreased from the cohorts born before to those born after the 1950s.

2.
Sci Rep ; 10(1): 7974, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32409744

RESUMO

Genetic factors explain a major proportion of human height variation, but differences in mean stature have also been found between socio-economic categories suggesting a possible effect of environment. By utilizing a classical twin design which allows decomposing the variation of height into genetic and environmental components, we tested the hypothesis that environmental variation in height is greater in offspring of lower educated parents. Twin data from 29 cohorts including 65,978 complete twin pairs with information on height at ages 1 to 69 years and on parental education were pooled allowing the analyses at different ages and in three geographic-cultural regions (Europe, North America and Australia, and East Asia). Parental education mostly showed a positive association with offspring height, with significant associations in mid-childhood and from adolescence onwards. In variance decomposition modeling, the genetic and environmental variance components of height did not show a consistent relation to parental education. A random-effects meta-regression analysis of the aggregate-level data showed a trend towards greater shared environmental variation of height in low parental education families. In conclusion, in our very large dataset from twin cohorts around the globe, these results provide only weak evidence for the study hypothesis.

3.
JCO Oncol Pract ; 16(10): e1169-e1180, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32469686

RESUMO

PURPOSE: Multiple myeloma (MM) treatment has changed tremendously, with significant improvement in patient out-comes. One group with a suboptimal benefit is patients with high-risk cytogenetics, as tested by conventional karyotyping or fluorescence in situ hybridization (FISH). Methodology for these tests has been published, but not necessarily standardized. METHODS: We address variability in the testing and reporting methodology for MM cytogenetics in the United States using the ongoing African American Multiple Myeloma Study (AAMMS). We evaluated clinical and cytogenetic data from 1,221 patients (1,161 with conventional karyotyping and 976 with FISH) tested between 1998 and 2016 across 58 laboratories nationwide. RESULTS: Interlab and intralab variability was noted for the number of cells analyzed for karyotyping, with a significantly higher number of cells analyzed in patients in whom cytogenetics were normal (P 5.0025). For FISH testing, CD138-positive cell enrichment was used in 29.7% of patients and no enrichment in 50% of patients, whereas the remainder had unknown status. A significantly smaller number of cells was analyzed for patients in which CD138 cell enrichment was used compared with those without such enrichment (median, 50 v 200; P, .0001). A median of 7 loci probes (range, 1-16) were used for FISH testing across all laboratories, with variability in the loci probed even within a given laboratory. Chromosome 13-related abnormalities were the most frequently tested abnormality (n5956; 97.9%), and t(14;16) was the least frequently tested abnormality (n 5 119; 12.2%). CONCLUSIONS: We report significant variability in cytogenetic testing across the United States for MM, potentially leading to variability in risk stratification, with possible clinical implications and personalized treatment approaches.

4.
Blood Adv ; 4(1): 181-190, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31935283

RESUMO

Persons of African ancestry (AA) have a twofold higher risk for multiple myeloma (MM) compared with persons of European ancestry (EA). Genome-wide association studies (GWASs) support a genetic contribution to MM etiology in individuals of EA. Little is known about genetic risk factors for MM in individuals of AA. We performed a meta-analysis of 2 GWASs of MM in 1813 cases and 8871 controls and conducted an admixture mapping scan to identify risk alleles. We fine-mapped the 23 known susceptibility loci to find markers that could better capture MM risk in individuals of AA and constructed a polygenic risk score (PRS) to assess the aggregated effect of known MM risk alleles. In GWAS meta-analysis, we identified 2 suggestive novel loci located at 9p24.3 and 9p13.1 at P < 1 × 10-6; however, no genome-wide significant association was noted. In admixture mapping, we observed a genome-wide significant inverse association between local AA at 2p24.1-23.1 and MM risk in AA individuals. Of the 23 known EA risk variants, 20 showed directional consistency, and 9 replicated at P < .05 in AA individuals. In 8 regions, we identified markers that better capture MM risk in persons with AA. AA individuals with a PRS in the top 10% had a 1.82-fold (95% confidence interval, 1.56-2.11) increased MM risk compared with those with average risk (25%-75%). The strongest functional association was between the risk allele for variant rs56219066 at 5q15 and lower ELL2 expression (P = 5.1 × 10-12). Our study shows that common genetic variation contributes to MM risk in individuals with AA.

5.
Obesity (Silver Spring) ; 27(5): 855-865, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30950584

RESUMO

OBJECTIVE: The objective of this study was to analyze how parental education modifies the genetic and environmental variances of BMI from infancy to old age in three geographic-cultural regions. METHODS: A pooled sample of 29 cohorts including 143,499 twin individuals with information on parental education and BMI from age 1 to 79 years (299,201 BMI measures) was analyzed by genetic twin modeling. RESULTS: Until 4 years of age, parental education was not consistently associated with BMI. Thereafter, higher parental education level was associated with lower BMI in males and females. Total and additive genetic variances of BMI were smaller in the offspring of highly educated parents than in those whose parents had low education levels. Especially in North American and Australian children, environmental factors shared by co-twins also contributed to the higher BMI variation in the low education level category. In Europe and East Asia, the associations of parental education with mean BMI and BMI variance were weaker than in North America and Australia. CONCLUSIONS: Lower parental education level is associated with higher mean BMI and larger genetic variance of BMI after early childhood, especially in the obesogenic macro-environment. The interplay among genetic predisposition, childhood social environment, and macro-social context is important for socioeconomic differences in BMI.


Assuntos
Índice de Massa Corporal , Interação Gene-Ambiente , Pais/educação , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Gêmeos , Adulto Jovem
6.
Leuk Lymphoma ; 60(6): 1429-1437, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30668190

RESUMO

DNA methylation (DNAm) silences gene expression and may play a role in immune dysregulation that is characteristic of adolescent/young adult Hodgkin lymphoma (AYAHL). We used the Infinium HumanMethylation27 BeadChip to quantify DNAm in blood (N = 9 pairs, mean age 57.4 y) or saliva (N = 36 pairs, mean age 50.0 y) from long-term AYAHL survivors and their unaffected co-twins. Epigenetic aging (DNAm age) was calculated using previously described methods and compared between survivors and co-twins using paired t-tests and analyses were stratified by sample type, histology, sex, age at sample collection and time since diagnosis. Differences in blood DNAm age were observed between survivors and unaffected co-twins (64.1 vs. 61.3 years, respectively, p = .04), especially in females (p = .01); no differences in saliva DNAm age were observed. Survivors and co-twins had 74 (in blood DNA) and 6 (in saliva DNA) differentially methylated loci. Our results suggest persistent epigenetic aging in AYAHL survivors long after HL cure.


Assuntos
Sobreviventes de Câncer , Metilação de DNA , Doença de Hodgkin/genética , Gêmeos Monozigóticos/genética , Adolescente , Adulto , Idoso , Biomarcadores Tumorais , Ilhas de CpG , Epigênese Genética , Feminino , Estudos de Associação Genética , Loci Gênicos , Predisposição Genética para Doença , Doença de Hodgkin/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
J Epidemiol ; 29(1): 18-25, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30270263

RESUMO

BACKGROUND: Inherited factors and maternal behaviors are thought to play an important role in the etiology of several congenital malformations. Twin studies can offer additional evidence regarding the contribution of genetic and lifestyle factors to common birth anomalies, but few large-scale studies have been reported. METHODS: We included data from twins (20,803 pairs) from the population-based California Twin Program. We compared concordance in monozygotic (MZ) to dizygotic (DZ) twins for the following birth anomalies: clubfoot, oral cleft, spina bifida, muscular dystrophy, deafness, cerebral palsy, strabismus, and congenital heart defects. Each birth anomaly was also examined for the associations with birth characteristics (birthweight and birth order) and parental exposures (age, smoking, and parental education). RESULTS: The overall prevalence of any selected birth anomaly in California twins was 38 per 1,000 persons, with a slightly decreasing trend from 1957-1982. For pairwise concordance in 6,752 MZ and 7,326 like-sex DZ twin pairs, high MZ:DZ concordance ratios were observed for clubfoot (CR 5.91; P = 0.043) and strabismus (CR 2.52; P = 0.001). Among the total 20,803 pairs, parental smoking was significantly associated with risk of spina bifida (OR 3.48; 95% CI, 1.48-8.18) and strabismus (OR 1.61; 95% CI, 1.28-2.03). A significant quadratic trend of increasing risk for clubfoot, spina bifida, and strabismus was found when examining whether father smoked, mother smoked, or both parents smoked relative to non-smoking parents (P = 0.029, 0.026, and 0.0005, respectively). CONCLUSIONS: Our results provide evidence for a multifactorial etiology underlying selected birth anomalies. Further research is needed to understand the biological mechanisms.


Assuntos
Anormalidades Congênitas/epidemiologia , Doenças em Gêmeos/epidemiologia , Gêmeos Dizigóticos/estatística & dados numéricos , Gêmeos Monozigóticos/estatística & dados numéricos , California/epidemiologia , Feminino , Interação Gene-Ambiente , Humanos , Recém-Nascido , Masculino , Prevalência , Sistema de Registros , Fumar/epidemiologia
9.
Twin Res Hum Genet ; 20(5): 395-405, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28975875

RESUMO

Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990-1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.


Assuntos
Sucesso Acadêmico , Modelos Genéticos , Gêmeos Dizigóticos , Gêmeos Monozigóticos , Estudos de Coortes , Feminino , Humanos , Masculino , Fatores Socioeconômicos
10.
Am J Clin Nutr ; 106(2): 457-466, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28679550

RESUMO

Background: Genes and the environment contribute to variation in adult body mass index [BMI (in kg/m2)], but factors modifying these variance components are poorly understood.Objective: We analyzed genetic and environmental variation in BMI between men and women from young adulthood to old age from the 1940s to the 2000s and between cultural-geographic regions representing high (North America and Australia), moderate (Europe), and low (East Asia) prevalence of obesity.Design: We used genetic structural equation modeling to analyze BMI in twins ≥20 y of age from 40 cohorts representing 20 countries (140,379 complete twin pairs).Results: The heritability of BMI decreased from 0.77 (95% CI: 0.77, 0.78) and 0.75 (95% CI: 0.74, 0.75) in men and women 20-29 y of age to 0.57 (95% CI: 0.54, 0.60) and 0.59 (95% CI: 0.53, 0.65) in men 70-79 y of age and women 80 y of age, respectively. The relative influence of unique environmental factors correspondingly increased. Differences in the sets of genes affecting BMI in men and women increased from 20-29 to 60-69 y of age. Mean BMI and variances in BMI increased from the 1940s to the 2000s and were greatest in North America and Australia, followed by Europe and East Asia. However, heritability estimates were largely similar over measurement years and between regions. There was no evidence of environmental factors shared by co-twins affecting BMI.Conclusions: The heritability of BMI decreased and differences in the sets of genes affecting BMI in men and women increased from young adulthood to old age. The heritability of BMI was largely similar between cultural-geographic regions and measurement years, despite large differences in mean BMI and variances in BMI. Our results show a strong influence of genetic factors on BMI, especially in early adulthood, regardless of the obesity level in the population.


Assuntos
Índice de Massa Corporal , Peso Corporal/genética , Meio Ambiente , Interação Gene-Ambiente , Obesidade/genética , Característica Quantitativa Herdável , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Austrália , Cultura , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte , Prevalência , Fatores Sexuais , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto Jovem
11.
Biol Sex Differ ; 8: 14, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28465822

RESUMO

BACKGROUND: The comparison of traits in twins from opposite-sex (OS) and same-sex (SS) dizygotic twin pairs is considered a proxy measure of prenatal hormone exposure. To examine possible prenatal hormonal influences on anthropometric traits, we compared mean height, body mass index (BMI), and the prevalence of being overweight or obese between men and women from OS and SS dizygotic twin pairs. METHODS: The data were derived from the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) database, and included 68,494 SS and 53,808 OS dizygotic twin individuals above the age of 20 years from 31 twin cohorts representing 19 countries. Zygosity was determined by questionnaires or DNA genotyping depending on the study. Multiple regression and logistic regression models adjusted for cohort, age, and birth year with the twin type as a predictor were carried out to compare height and BMI in twins from OS pairs with those from SS pairs and to calculate the adjusted odds ratios and 95% confidence intervals for being overweight or obese. RESULTS: OS females were, on average, 0.31 cm (95% confidence interval (CI) 0.20, 0.41) taller than SS females. OS males were also, on average, taller than SS males, but this difference was only 0.14 cm (95% CI 0.02, 0.27). Mean BMI and the prevalence of overweight or obesity did not differ between males and females from SS and OS twin pairs. The statistically significant differences between OS and SS twins for height were small and appeared to reflect our large sample size rather than meaningful differences of public health relevance. CONCLUSIONS: We found no evidence to support the hypothesis that prenatal hormonal exposure or postnatal socialization (i.e., having grown up with a twin of the opposite sex) has a major impact on height and BMI in adulthood.


Assuntos
Estatura , Índice de Massa Corporal , Gêmeos Dizigóticos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
PLoS One ; 12(3): e0174457, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28334025

RESUMO

A proportion of classical Hodgkin lymphomas harbor the Epstein Barr virus (EBV). We previously demonstrated that associations between Human Leukocyte Antigen (HLA) alleles and susceptibility to EBV+ classical Hodgkin lymphoma differ between European and Chinese populations. Data on Hispanic populations is missing. Here we examined the association between HLA type, tumor cell HLA expression and other characteristics in Hispanic Hodgkin lymphoma patients. Hispanic Hodgkin lymphoma patients diagnosed at the Los Angeles County-University of Southern California Medical Center from 2000-2012 were included (n = 65). Formalin-fixed paraffin-embedded tumor tissue was analyzed for EBV by in situ hybridization and for HLA class I and class II expression by immunohistochemistry. HLA typing was performed by HLA-A specific quantitative PCR of genomic DNA from tissue. Thirty patients (46%) had EBV+ tumors. Expression of HLA class I (p = 0.0006) was significantly associated with EBV+ tumor status in Hispanic patients, similar to Europeans and Chinese. A positive association between HLA class II expression and EBV+ tumor status, as present in large studies in Europeans, was not found (p = 0.06). The prevalences of the specific European HLA-A*01 risk and European HLA-A*02 protective types were not significantly associated with EBV+ tumors among these Hispanic patients, however numbers were too low to draw firm conclusions. The HLA-A*02:07 allele, that is associated with EBV+ Hodgkin lymphoma in Chinese, was absent. In conclusion, the association between EBV positivity in tumor cells and HLA class I expression appears to be consistent across different populations. Larger studies in Hispanics are needed to evaluate HLA allele susceptibility associations.


Assuntos
Infecções por Vírus Epstein-Barr/imunologia , Antígenos HLA/genética , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Frequência do Gene , Doença de Hodgkin/genética , Doença de Hodgkin/virologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
Elife ; 52016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27964777

RESUMO

Human height variation is determined by genetic and environmental factors, but it remains unclear whether their influences differ across birth-year cohorts. We conducted an individual-based pooled analysis of 40 twin cohorts including 143,390 complete twin pairs born 1886-1994. Although genetic variance showed a generally increasing trend across the birth-year cohorts, heritability estimates (0.69-0.84 in men and 0.53-0.78 in women) did not present any clear pattern of secular changes. Comparing geographic-cultural regions (Europe, North America and Australia, and East Asia), total height variance was greatest in North America and Australia and lowest in East Asia, but no clear pattern in the heritability estimates across the birth-year cohorts emerged. Our findings do not support the hypothesis that heritability of height is lower in populations with low living standards than in affluent populations, nor that heritability of height will increase within a population as living standards improve.


Assuntos
Estatura/genética , Exposição Ambiental , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Saúde Global , Humanos , Masculino , Pessoa de Meia-Idade , Gêmeos , Adulto Jovem
14.
Cancer Epidemiol Biomarkers Prev ; 25(12): 1609-1618, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27587788

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) in European populations have identified genetic risk variants associated with multiple myeloma. METHODS: We performed association testing of common variation in eight regions in 1,318 patients with multiple myeloma and 1,480 controls of European ancestry and 1,305 patients with multiple myeloma and 7,078 controls of African ancestry and conducted a meta-analysis to localize the signals, with epigenetic annotation used to predict functionality. RESULTS: We found that variants in 7p15.3, 17p11.2, 22q13.1 were statistically significantly (P < 0.05) associated with multiple myeloma risk in persons of African ancestry and persons of European ancestry, and the variant in 3p22.1 was associated in European ancestry only. In a combined African ancestry-European ancestry meta-analysis, variation in five regions (2p23.3, 3p22.1, 7p15.3, 17p11.2, 22q13.1) was statistically significantly associated with multiple myeloma risk. In 3p22.1, the correlated variants clustered within the gene body of ULK4 Correlated variants in 7p15.3 clustered around an enhancer at the 3' end of the CDCA7L transcription termination site. A missense variant at 17p11.2 (rs34562254, Pro251Leu, OR, 1.32; P = 2.93 × 10-7) in TNFRSF13B encodes a lymphocyte-specific protein in the TNF receptor family that interacts with the NF-κB pathway. SNPs correlated with the index signal in 22q13.1 cluster around the promoter and enhancer regions of CBX7 CONCLUSIONS: We found that reported multiple myeloma susceptibility regions contain risk variants important across populations, supporting the use of multiple racial/ethnic groups with different underlying genetic architecture to enhance the localization and identification of putatively functional alleles. IMPACT: A subset of reported risk loci for multiple myeloma has consistent effects across populations and is likely to be functional. Cancer Epidemiol Biomarkers Prev; 25(12); 1609-18. ©2016 AACR.


Assuntos
Grupo com Ancestrais do Continente Africano/genética , Grupo com Ancestrais do Continente Europeu/genética , Predisposição Genética para Doença , Mieloma Múltiplo/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Feminino , Loci Gênicos , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/metabolismo , Complexo Repressor Polycomb 1/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Repressoras/genética , Proteína Transmembrana Ativadora e Interagente do CAML/genética
15.
Am J Clin Nutr ; 104(2): 371-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27413137

RESUMO

BACKGROUND: Both genetic and environmental factors are known to affect body mass index (BMI), but detailed understanding of how their effects differ during childhood and adolescence is lacking. OBJECTIVES: We analyzed the genetic and environmental contributions to BMI variation from infancy to early adulthood and the ways they differ by sex and geographic regions representing high (North America and Australia), moderate (Europe), and low levels (East Asia) of obesogenic environments. DESIGN: Data were available for 87,782 complete twin pairs from 0.5 to 19.5 y of age from 45 cohorts. Analyses were based on 383,092 BMI measurements. Variation in BMI was decomposed into genetic and environmental components through genetic structural equation modeling. RESULTS: The variance of BMI increased from 5 y of age along with increasing mean BMI. The proportion of BMI variation explained by additive genetic factors was lowest at 4 y of age in boys (a(2) = 0.42) and girls (a(2) = 0.41) and then generally increased to 0.75 in both sexes at 19 y of age. This was because of a stronger influence of environmental factors shared by co-twins in midchildhood. After 15 y of age, the effect of shared environment was not observed. The sex-specific expression of genetic factors was seen in infancy but was most prominent at 13 y of age and older. The variance of BMI was highest in North America and Australia and lowest in East Asia, but the relative proportion of genetic variation to total variation remained roughly similar across different regions. CONCLUSIONS: Environmental factors shared by co-twins affect BMI in childhood, but little evidence for their contribution was found in late adolescence. Our results suggest that genetic factors play a major role in the variation of BMI in adolescence among populations of different ethnicities exposed to different environmental factors related to obesity.


Assuntos
Índice de Massa Corporal , Meio Ambiente , Interação Gene-Ambiente , Variação Genética , Obesidade/etiologia , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adolescente , Adulto , Fatores Etários , Austrália , Criança , Pré-Escolar , Europa (Continente) , Extremo Oriente , Feminino , Humanos , Lactente , Masculino , América do Norte , Obesidade/etnologia , Obesidade/genética , Fatores Sexuais , Adulto Jovem
16.
Sci Rep ; 6: 28496, 2016 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-27333805

RESUMO

Height variation is known to be determined by both genetic and environmental factors, but a systematic description of how their influences differ by sex, age and global regions is lacking. We conducted an individual-based pooled analysis of 45 twin cohorts from 20 countries, including 180,520 paired measurements at ages 1-19 years. The proportion of height variation explained by shared environmental factors was greatest in early childhood, but these effects remained present until early adulthood. Accordingly, the relative genetic contribution increased with age and was greatest in adolescence (up to 0.83 in boys and 0.76 in girls). Comparing geographic-cultural regions (Europe, North-America and Australia, and East-Asia), genetic variance was greatest in North-America and Australia and lowest in East-Asia, but the relative proportion of genetic variation was roughly similar across these regions. Our findings provide further insights into height variation during childhood and adolescence in populations representing different ethnicities and exposed to different environments.


Assuntos
Estatura , Meio Ambiente , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adolescente , Austrália , Criança , Pré-Escolar , Estudos de Coortes , Europa (Continente) , Extremo Oriente , Feminino , Interação Gene-Ambiente , Variação Genética , Humanos , Lactente , Masculino , América do Norte , Adulto Jovem
17.
Am J Epidemiol ; 182(5): 417-25, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26271116

RESUMO

We evaluated the association between common immune system-altering experiences and non-Hodgkin lymphoma (NHL) risk using a case-control study of 162 like-sex twin pairs discordant for NHL, identified from the International Twin Study. Information on medical history and evidence of childhood exposure to microbes was obtained by questionnaire from 1998 to 2002. Conditional logistic regression was used to estimate odds ratios and 95% confidence intervals. Intra-twin-pair agreement between twins on individual exposures was high (76%-97%). A negative association between NHL and seasonal hay fever (odds ratio (OR) = 0.28, 95% confidence interval (CI): 0.10, 0.75) and certain allergies (OR = 0.29, 95% CI: 0.13, 0.68) was observed. The number of atopic diseases was negatively associated with NHL (P for trend = 0.0003). A history of infectious mononucleosis was negatively associated with NHL risk (OR = 0.35, 95% CI: 0.14, 0.90). NHL risk was associated with more frequent childhood exposure to microbes during early life (P for trend = 0.04). No differences in association by NHL subtype were observed, although statistical power for these comparisons was low. These observations support the hypothesis that immune-related exposures, especially atopy, are associated with decreased NHL risk. Use of the within-twin-pair study design mitigates confounding by genome, family structure, and unmeasured characteristics of early childhood factors.


Assuntos
Infecções por Vírus Epstein-Barr/epidemiologia , Hipersensibilidade/epidemiologia , Linfoma não Hodgkin/epidemiologia , Adulto , Idoso , Apendicectomia/estatística & dados numéricos , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Rinite Alérgica Sazonal/epidemiologia , Fatores de Risco , Tonsilectomia/estatística & dados numéricos
18.
Am J Epidemiol ; 178(4): 551-8, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23585330

RESUMO

Adult height is determined by genetics and childhood nutrition, but childhood infections may also play a role. Monozygotic twins are genetically matched and offer an advantage when identifying environmental determinants. In 2005-2007, we examined the association of childhood infections with adult height in 140 height-discordant monozygotic twin pairs from the California Twin Program. To obtain information on childhood infections and growth, we interviewed the mothers of monozygotic twins who differed in self-reported adult height by at least 1-inch (2.5 cm). Within-pair differences in the relative frequency of childhood infections were highly correlated, especially within age groups. A conditional logistic regression analysis demonstrated that more reported episodes of febrile illness occurred in the twin with shorter stature (odds ratio = 2.00, 95% confidence interval: 1.18, 3.40). The association was strongest for differences in the relative frequency of infection during the toddler years (ages 1-5: odds ratio = 3.34, 95% confidence interval: 1.47, 7.59) and was similar when restricted to twin pairs of equal birth length. The association was not explained by differential nutritional status. Measures of childhood infection were associated with height difference in monozygotic twin pairs, independent of genome, birth length, and available measures of diet.


Assuntos
Estatura , Desenvolvimento Infantil , Doenças Transmissíveis/complicações , Gêmeos Monozigóticos/estatística & dados numéricos , Adolescente , Adulto , Antibacterianos/uso terapêutico , California , Estudos de Casos e Controles , Criança , Pré-Escolar , Doenças Transmissíveis/tratamento farmacológico , Feminino , Febre , Humanos , Lactente , Entrevistas como Assunto , Modelos Logísticos , Masculino , Mães , Tempo
19.
Twin Res Hum Genet ; 16(1): 366-70, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23218448

RESUMO

The study of twin subjects permits the documentation of crude heritability and may promote the identification of specific causal alleles. We believe that at the current time, the chief research advantage of twins as subjects, especially monozygotic twins, is that the commonality of their genetic and cultural identity simplifies the interpretation of biological associations. In order to study genetic and environmental determinants of cancer and chronic diseases, we developed two twin registries, maintained at the University of Southern California: The International Twin Study (ITS) and the California Twin Program (CTP). The ITS is a volunteer registry of twins with cancer and chronic disease consisting of 17,245 twin pairs affected by cancer and chronic disease, respectively, ascertained by advertising in periodicals from 1980-1991. The CTP is a population-based registry of California-born twin pairs ascertained by linking the California birth records to the State Department of Motor Vehicles. Over 51,000 individual California twins representing 36,965 pairs completed and returned 16-page questionnaires. Cancer diagnoses in the California twins are updated by regular linkage to the California Cancer Registry. Over 5,000 cancer patients are represented in the CTP. Twins from both registries have participated extensively in studies of breast cancer, melanoma, lymphoma, multiple sclerosis, systemic lupus erythematosus, diabetes mellitus type 1, mammographic density, smoking, and other traits and conditions.


Assuntos
Doenças em Gêmeos/epidemiologia , Neoplasias/epidemiologia , Sistema de Registros , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adolescente , Adulto , Idoso , California/epidemiologia , Doença Crônica , Estudos de Coortes , Doenças em Gêmeos/genética , Feminino , Interação Gene-Ambiente , Humanos , Agências Internacionais , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Gêmeos Dizigóticos/estatística & dados numéricos , Gêmeos Monozigóticos/estatística & dados numéricos , Adulto Jovem
20.
Blood ; 119(2): 469-75, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-22086417

RESUMO

Nodular sclerosing Hodgkin lymphoma (NSHL) is a distinct, highly heritable Hodgkin lymphoma subtype. We undertook a genome-wide meta-analysis of 393 European-origin adolescent/young adult NSHL patients and 3315 controls using the Illumina Human610-Quad Beadchip and Affymetrix Genome-Wide Human SNP Array 6.0. We identified 3 single nucleotide polymorphisms (SNPs) on chromosome 6p21.32 that were significantly associated with NSHL risk: rs9268542 (P = 5.35 × 10(-10)), rs204999 (P = 1.44 × 10(-9)), and rs2858870 (P = 1.69 × 10(-8)). We also confirmed a previously reported association in the same region, rs6903608 (P = 3.52 × 10(-10)). rs204999 and rs2858870 were weakly correlated (r(2) = 0.257), and the remaining pairs of SNPs were not correlated (r(2) < 0.1). In an independent set of 113 NSHL cases and 214 controls, 2 SNPs were significantly associated with NSHL and a third showed a comparable odds ratio (OR). These SNPs are found on 2 haplotypes associated with NSHL risk (rs204999-rs9268528-rs9268542-rs6903608-rs2858870; AGGCT, OR = 1.7, P = 1.71 × 10(-6); GAATC, OR = 0.4, P = 1.16 × 10(-4)). All individuals with the GAATC haplotype also carried the HLA class II DRB1*0701 allele. In a separate analysis, the DRB1*0701 allele was associated with a decreased risk of NSHL (OR = 0.5, 95% confidence interval = 0.4, 0.7). These data support the importance of the HLA class II region in NSHL etiology.


Assuntos
Cromossomos Humanos Par 6/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Haplótipos/genética , Doença de Hodgkin/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
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