Minor physical anomalies

Minor physical anomalies (MPAs) are relatively minor (typically painless and, in themselves, harmless) congenital physical abnormalities consisting of features such as low-seated ears, single transverse palmar crease, telecanthus, micrognathism a furrowed tongue. While MPAs may have a genetic basis, they might also be caused by factors in the fetal environment: anoxia, bleeding, or infection. MPAs have been linked to disorders of pregnancy and are thought by some to be a marker for insults to the fetal neural development towards the end of the first trimester. Thus, in the neurodevelopmental literature, they are seen as indirect indications of inferferences with brain development. In studies of children and adolescents with conduct problems, such markers have been linked to some extent to impulsivity and aggressiveness.

MPAs have been studied in autism, down syndrome, and in schizophrenia. A 2008 meta-analysis found that MPAs are significantly increased in the autistic population.^[1] 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.^[2]

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, ^[3] 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:^[4] A study in the American Journal of Psychiatry by Trixler et al.: ^[5] 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.^[6] It can be caused by perinatal hypoxia: ^[7]

References

1. ^ Ozgen HM, Hop JW, Hox JJ, Beemer FA, van Engeland H (2008). "Minor physical anomalies in autism: a meta-analysis". Mol Psychiatry 15 (3): 300–7. doi:10.1038/mp.2008.75. PMID 18626481. 
2. ^ Ismail, B I, Cantor-Graso, E, and McNeil, T P (1998). "Minor Physical Anomalies in Schizophrenic Patients and their Siblings," American Journal of Psychiatry, 155:1695-1702
3. ^ Baher Ismail, Elizabeth Cantor-Graae, Thomas F McNeil."Minor physical anomalies in schizophrenic patients and their siblings" The American Journal of Psychiatry. Washington: Dec 1998. Vol. 155, Iss. 12; pg. 1695. Cleft palates are partly attributable to hypoxia: Guillermo Millicovsky, Malcolm C. Johnston, Proceedings of the National Academy of Sciences of the United States of America, Vol. 78, No. 9, [Part 2: Biological Sciences] (Sep., 1981), pp. 5722-5723
4. ^ Rob Helton, Jiankun Cui, John R. Scheel, Julie A. Ellison, Chris Ames, Claire Gibson, Barbara Blouw, Ling Ouyang, Ioannis Dragatsis, Scott Zeitlin, Randall S. Johnson, Stuart A. Lipton, and Carrolee Barlow , April 20 2005, Brain-Specific knock- out of Hypoxia inducible factor -1alpha, reduces - rather than increases hypoxix-ischemic damage, The Journal of Neuroscience, pp4099-4107, http://www.jneurosci.org/cgi/content/full/25/16/4099/TBL2.
5. ^ Mátyás Trixler, M.D., Ph.D., Tamás Tényi, M.D., Györgyi Csábi, M.D.,Gizella Szabó, M.D., and Károly Méhes, M.D., Ph.D., Sc.D,; 1997 Informative Morphogenetic Variants in Patients With Schizophrenia ,and Alcohol-Dependent Patients: Beyond the Waldrop Scale, 154:691–693 . http://ajp.psychiatryonline.org/cgi/reprint/154/5/691.pdf
6. ^ See Toyota et al., (2004) Vol 13(5) "Association between schizophrenia with ocular misalignment and polyalanine length variation in PMX2B"; Human Molecular Genetics; p551; (http://hmg.oxfordjournals.org/cgi/content/abstract/13/5/551 as of 13-12-07).
7. ^ R. Huo, S.K. Burden, C.S. Hoyt and W.V. Good; "Chronic cortical visual impairment in children: aetioloy, prognosis and associated neurological deficits"; The British Journal Of Ophthalmology [Br J Ophthalmol], 1999 Jun; Vol. 83 (6).

Further reading

• Habel, A, Elhadt, N, Sommerlad, B, Powell, J (2005) 'Delayed detection of cleft palate: an audit of newborn examination', Archive of Diseases in Childhood, 91, p238.

Psychiatry, V 155, Iss 12.

• Raine, A. (2002). Annotation: The role of prefrontal deficits, low autonomic arousal, and early health factors in the development of antisocial and aggressive behavior in children. Journal of Child Psychology and Psychiatry, 43(4), 417-434.