?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Subtle+signs+of+prenatal+maldevelopment+of+the+hand+ectoderm+in+schizophrenia%3A+a+preliminary+monozygotic+twin+study&rft.creator=Bracha%2C+HS&rft.creator=Torrey%2C+EF&rft.creator=Bigelow%2C+LB&rft.creator=Lohr%2C+JB&rft.creator=Linington%2C+BB&rft.subject=Neuropsychiatry&rft.subject=Neurology&rft.description=Genes+that+predispose+to+psychosis+may+act+by+making+individuals+more+vulnerable+to+the+disruptive+effects+of+various+prenatal+insults.+Fetal+organogenesis+is+mostly+completed+in+the+first+prenatal+trimester.+The+second+trimester+is+a+critical+period+of+massive+neuronal+migration+from+the+periventricular+germinal+matrix+to+the+cortex.+A+peripheral+appendage+developing+simultaneously+with+this+neural+migration+to+the+cortex+is+the+distal+upper+limb.+The+ectodermal+cells+of+the+fetal+upper+limb+migrate+to+form+the+hand+skin+during+the+fourth+and+fifth+months+of+gestation+(first+two-thirds+of+the+second+prenatal+trimester).+Discrepancies+in+hand+morphology+between+two+identical+(monozygotic+%5BMZ%5D)+co-twins+may+be+temporal+markers%2C+that+is%2C+the+%22fossilized%22+evidence+of+various+ischemic+and+other+nongenetic+insults+that+may+have+affected+one+fetus+more+than+his+MZ+co-twin+during+that+early+part+of+the+second+trimester.+In+twins%2C+prenatal+insults+(e.g.%2C+ischemia)+frequently+do+not+affect+both+co-twins+to+the+same+extent%2C+so+we+examined+seven+putative+markers+of+prenatal+injury+to+the+hand+in+24+MZ+twin+pairs+discordant+for+schizophrenia+or+delusional+disorder.+Compared+with+well+co-twins%2C+the+affected+co-twins+had+significantly+higher+total+scores+of+fourth-+and+fifth-month+dysmorphological+hand+anomalies.%0A&rft.date=1991-10&rft.type=Journal+(Paginated)&rft.type=NonPeerReviewed&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Fcogprints.org%2F5318%2F1%2FBracha_et_al.%252C_Subtle_Signs_of_Prenatal_Maldevelopment.PDF&rft.identifier=++Bracha%2C+HS+and+Torrey%2C+EF+and+Bigelow%2C+LB+and+Lohr%2C+JB+and+Linington%2C+BB++(1991)+Subtle+signs+of+prenatal+maldevelopment+of+the+hand+ectoderm+in+schizophrenia%3A+a+preliminary+monozygotic+twin+study.++%5BJournal+(Paginated)%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F5318%2F