CACNA1A and neural tube defect: Two unexpected results were obtained from these experiments: i) the very low vitamin E content was similar in SR-BI−/− embryos with NTD (SR-BI−/− NTD) or with normal neural tube closure (nSR-BI−/−) and ii) maternal supplementation with α-tocopherol did not increase the embryonic vitamin E levels, despite its striking effect on NTD prevention (Fig. 2a).