title: Quality Analysis of DNA from Cord Blood Buffy Coat: The Best Neonatal DNA Source for Epidemiological Studies?
abstract: BACKGROUND
  Umbilical cord blood is an economical and easy to obtain source of high-quality neonatal genomic DNA. However, although large numbers of cord blood samples have been collected, information on the yield and quality of the DNA extracted from cord blood is scarce. Moreover, considerable doubt still exists on the utility of the buffy coat instead of whole blood as a DNA source.
  
  
  METHODS
  We compared the sample storage and DNA extraction costs for whole blood, buffy coat, and all-cell pellet. We evaluated three different DNA purification kits and selected the most suitable one to purify 1011 buffy coat samples. We determined the DNA yield and optical density (OD) ratios and analyzed 48 single-nucleotide polymorphisms using time-of-flight mass spectrometry (TOF MS). We also analyzed eight possible preanalytical variables that may correlate with DNA yield or quality.
  
  
  RESULTS
  Buffy coat was the most economical and least labor-intensive source for sample storage and DNA extraction. The average yield of genomic DNA from 200 μL of buffy coat sample was 16.01 ± 8.00 μg, which is sufficient for analytic experiments. The mean A260/A280 ratio and the mean A260/A230 ratio were 1.89 ± 0.09 and 1.95 ± 0.66, respectively. More than 99.5% of DNA samples passed the TOF MS test. Only hemolysis showed a strong correlation with OD ratios of DNA, but not with yield.
  
  
  CONCLUSIONS
  Our findings show that cord blood buffy coat yields high-quality DNA in sufficient quantities to meet the requirements of experiments. Buffy coat was also found to be the most economic, efficient, and stable source of genomic DNA.
authors.affiliation: 1 MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine , Shanghai, China .
authors.forename: Guangdi
authors.initials: G
authors.lastname: Zhou
authors.affiliation: 2 Department of Obstetrics and Gynecology, Changhai Hospital Affiliated to the Second Military Medical University , Shanghai, China .
authors.forename: Qin
authors.initials: Q
authors.lastname: Li
authors.affiliation: 3 Department of Pediatrics, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine , Shanghai, China .
authors.forename: Lisu
authors.initials: L
authors.lastname: Huang
authors.affiliation: 1 MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine , Shanghai, China .
authors.forename: Yuhang
authors.initials: Y
authors.lastname: Wu
authors.affiliation: 1 MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine , Shanghai, China .
authors.forename: Meiqin
authors.initials: M
authors.lastname: Wu
authors.affiliation: 1 MOE-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine , Shanghai, China .
authors.forename: Weiye C
authors.initials: WC
authors.lastname: Wang
mesh_terms: D058621:Blood Buffy Coat / Q000378:metabolism*; D004247:DNA / Q000235:genetics*; D005312:Fetal Blood / Q000378:metabolism*; D006801:Humans; D007231:Infant, Newborn; D013058:Mass Spectrometry; D020641:Polymorphism, Single Nucleotide
chemical_list: D004247:DNA