Exome-wide assessment of isolated biliary atresia: A report from the National Birth Defects Prevention Study using child-parent trios and a case-control design to identify novel rare variants.

The etiology of biliary atresia (BA) is unknown, but recent studies suggest a role for rare protein-altering variants (PAVs). Exome sequencing data from the National Birth Defects Prevention Study on 54 child-parent trios, one child-mother duo, and 1513 parents of children with other birth defects were analyzed. Most (91%) cases were isolated BA. We performed (1) a trio-based analysis to identify rare de novo, homozygous, and compound heterozygous PAVs and (2) a case-control analysis using a sequence kernel-based association test to identify genes enriched with rare PAVs. While we replicated previous findings on PKD1L1, our results do not suggest that recurrent de novo PAVs play important roles in BA susceptibility. In fact, our finding in NOTCH2, a disease gene associated with Alagille syndrome, highlights the difficulty in BA diagnosis. Notably, IFRD2 has been implicated in other gastrointestinal conditions and warrants additional study. Overall, our findings strengthen the hypothesis that the etiology of BA is complex.

Infant Mortality Attributable to Birth Defects - United States, 2003-2017.

Birth defects are a leading cause of infant mortality in the United States, accounting for 20.6% of infant deaths in 2017 (1). Rates of infant mortality attributable to birth defects (IMBD) have generally declined since the 1970s (1-3). U.S. linked birth/infant death data from 2003-2017 were used to assess trends in IMBD. Overall, rates declined 10% during 2003-2017, but decreases varied by maternal and infant characteristics. During 2003-2017, IMBD rates decreased 4% for infants of Hispanic mothers, 11% for infants of non-Hispanic black (black) mothers, and 12% for infants of non-Hispanic white (white) mothers. In 2017, these rates were highest among infants of black mothers (13.3 per 10,000 live births) and were lowest among infants of white mothers (9.9). During 2003-2017, IMBD rates for infants who were born extremely preterm (20-27 completed gestational weeks), full term (39-40 weeks), and late term/postterm (41-44 weeks) declined 20%-29%; rates for moderate (32-33 weeks) and late preterm (34-36 weeks) infants increased 17%. Continued tracking of IMBD rates can help identify areas where efforts to reduce IMBD are needed, such as among infants born to black and Hispanic mothers and those born moderate and late preterm (32-36 weeks).

Association Between Infant Mortality Attributable to Birth Defects and Payment Source for Delivery - United States, 2011-2013.

Birth defects are a leading cause of infant mortality in the United States (1), accounting for approximately 20% of infant deaths. The rate of infant mortality attributable to birth defects (IMBD) in the United States in 2014 was 11.9 per 10,000 live births (1). Rates of IMBD differ by race/ethnicity (2), age group at death (2), and gestational age at birth (3). Insurance type is associated with survival among infants with congenital heart defects (CHD) (4). In 2003, a checkbox indicating principal payment source for delivery was added to the U.S. standard birth certificate (5). To assess IMBD by payment source for delivery, CDC analyzed linked U.S. birth/infant death data for 2011-2013 from states that adopted the 2003 revision of the birth certificate. The results indicated that IMBD rates for preterm (<37 weeks of gestation) and term (≥37 weeks) infants whose deliveries were covered by Medicaid were higher during the neonatal (<28 days) and postneonatal (≥28 days to <1 year) periods compared with infants whose deliveries were covered by private insurance. Similar differences in postneonatal mortality were observed for the three most common categories of birth defects listed as a cause of death: central nervous system (CNS) defects, CHD, and chromosomal abnormalities. Strategies to ensure quality of care and access to care might reduce the difference between deliveries covered by Medicaid and those covered by private insurance.