Although the exome dataset of the father of proband SB1A (SB1C) was not available to screen for a de novo or recessive inheritance pattern, it would be interesting to further test if the novel variant in VANGL1 (Chr01:116206438C>A; planar cell polarity gene) that was found in proband SB1A and predicted to have a damaging effect on the protein, could play an additive or combinatorial role with the EFNB1 variant (rs772228172) in spina bifida susceptibility. The gene discussed is EFNB1; the disease is spina bifida.