Answer:
Rh-negative mothers and Rh-positive baby boys.
Step-by-step explanation:
At least three research studies have proven that Rh incompatibility can be a potential risk factor for schizophrenia, this happens because the mother is Rh-negative (no protein coded) and the fetus is Rh-positive and therefore the mother's immune system responds to the baby's Rh protein leading to hypoxia, anemia and abnormal glial development with a higher risk for baby boys.
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