MPAs have been studied in autism and in schizophrenia. A 2008 meta-analysis found that MPAs are significantly increased in the autistic population. A 1998 study found that 60% of its schizophrenic sample and 38% of their siblings had 6 or more minor physical anomalies (especially in the craniofacial area), while only 5% of the control group showed that many.
Some Minor Physical Anomalies related to schizophrenia have a hypoxic contribution to their formation.
These anomalies are thought to reflect changes in the brain as both are derived from the ectoderm.
Several minor physical anomalies are attributable in part by hypoxia. The most often cited minor physical anomaly: high arched palate, is described in articles as a microform of a cleft palate, The vaulted palate caused by nasal obstruction and consequent mouth breathing, without the lateralising effect of the tongue can produce hypoxia at night but is not reported as contributing to schizophrenia.
Other malformations are reported only sporadically. Capillary Malformation is induced by RASA1 mutation and can be changed by hypoxia: A study in the American Journal of Psychiatry by Trixler et al: found hemangiomas to be highly significant in schizophrenia, and one of the authors said hemangiomas would include any birthmark which hadn't faded by adulthood - as this was suspected as abnormal (although he added the correlation wasn't high)(Pers. Comm). Exotropia is reported as having low correlation and high significance as well. It can be caused by perinatal hypoxia:
Psychiatry, V 155, Iss 12.