title: Association of genetic ancestry with preterm delivery and related traits among African American mothers.
abstract: OBJECTIVE
  In the United States, the rate of preterm delivery (PTD) is higher in African Americans (17.8%) than non-Hispanic whites (11.5%). Such disparity cannot be fully explained by differences in socioenvironmental factors.
  
  
  METHODS
  We genotyped 812 mothers in a case-control PTD study at Boston Medical Center who self-reported their ethnicity as "black." Regression analysis and Wilcoxon rank-sum test were applied to evaluate ancestral distribution and the association between genetic ancestry and PTD-related traits, as well as the potential confounding effect of population stratification.
  
  
  RESULTS
  The estimated African ancestral proportion was 0.90 +/- 0.13. We found significant associations of ancestral proportion with PTD as a whole and PTD subgrouped by the presence of maternal hypertensive disorders. We did not observe significant confounding as a result of population stratification in this case-control PTD study.
  
  
  CONCLUSIONS
  Our data underline the need for more intensive investigation of genetic admixture in African Americans to identify novel susceptibility genes of PTD.
authors.affiliation: Mary Ann and J Milburn Smith Child Health Research Program, Children's Memorial Hospital and Children's Memorial Research Center, Chicago, IL 60614-3394 , USA. htsai@childrensmemorial.org
authors.forename: Hui-Ju
authors.initials: HJ
authors.lastname: Tsai
authors.forename: Yunxian
authors.initials: Y
authors.lastname: Yu
authors.forename: Shanchun
authors.initials: S
authors.lastname: Zhang
authors.forename: Colleen
authors.initials: C
authors.lastname: Pearson
authors.forename: Katherin
authors.initials: K
authors.lastname: Ortiz
authors.forename: Xiping
authors.initials: X
authors.lastname: Xu
authors.forename: Howard
authors.initials: H
authors.lastname: Bauchner
authors.forename: Barry
authors.initials: B
authors.lastname: Zuckerman
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Wang
mesh_terms: D000328:Adult; D001741:Black or African American / Q000235:genetics*; D016022:Case-Control Studies; D015986:Confounding Factors, Epidemiologic; D005260:Female; D020022:Genetic Predisposition to Disease / Q000208:ethnology*; D005838:Genotype; D006801:Humans; D011247:Pregnancy; D047928:Premature Birth / Q000208:ethnology* / Q000235:genetics; D012907:Smoking / Q000453:epidemiology; D044465:White People / Q000235:genetics; D055815:Young Adult