SLC39A8 and lymphopenia: Thymic atrophy, lymphopenia, and compromised cell- and antibody-mediated responses that cause increased rates of infections of longer duration are the immunological hallmarks of zinc deficiency in adult humans and mice [41]; however, in Slc39a8(neo/neo) fetuses and newborns, we did not observe any decrease in thymus weight (Table 2)–suggesting that chronic zinc deficiency in adults is distinctly different from what is seen here in our mouse in utero model, with regard to effects of ZIP8 deficiency on hematopoiesis.