Determining gestational age using genome methylation profile

Methods The inclusion criteria were: singleton pregnancy, accurate dating of the gestation by the current methods of LMP, CRL, and normal fetal anatomy scan. The exclusion criteria were: babies that were suspected to have a genetic syndromes or anomalies during the pediatrician’s examination. Whole blood samples were collected from the umbilical cord of newborns (gestational age 24-40 weeks) along with the respective placental samples. In addition, the newborns gestational age was further clinically assessed using Ballard score. DNA was extracted from whole blood and placenta samples. Global methylation pattern was determined by RRBS assay (reduced representation bisulfite sequencing). For bioinformatics analysis the samples were divided into a ‘Train’ group (5 samples each from early and late gestational age), and a ‘Test’ group (all the remaining samples). Genomic regions that have different DNA Methylated Regions (DMRs) were identified according to high stringency criteria.