Finger patterns and age of onset for the determination of the parent-of-origin in the transmission of schizophrenia

SUMMARY: Dermatoglyphic traits which are reported to be largely determined by genes could be considered as phenotypic characterestics and if the same are expressed through generations in schizophrenic families it can be speculated to serve as genetic markers for schizophrenia. Another factor that might be influenced by genes is the age of onset of the illness in the offspring and the parent of origin. OBJECTIVE: This study was aimed to elucidate the occurrence of identical finger patterns in the schizophrenic patients and their affected parents. The other objective was to assess the age of onset of the illness in them. METHODS: Forty six schizophrenic patients in whom one of the parents was also affected with schizophrenia or related disorders were recruited. Of these pairs 29 were taken up for finger patterns analysis, with an equal number of control group pairs. 35 proband and parent pairs were investigated for the age of onset of the illness. RESULTS: The frequency of occurrence of identical patterns in the right thumbs of proband and their affected mother pairs was significantly more than between the proband and their affected father pairs. Additionally, the number of identical patterns was also more in the right thumbs of proband and their affected mother pairs compared with the control group. The difference between the mean age of onset of the illness in the probands and their affected fathers was more than between the probands and their affected mothers. CONCLUSION: The genetic association of schizophrenic patients with the affected maternal side appear to be more stronger than with the paternal side.