A 39-year followup of the Genain quadruplets

The Genains, a unique group of monozygotic female quadruplets, all develope d a schizophrenic disorder by age 24, They have been studied since the 1950 s, because of the rarity of this occurrence (estimated to be one in 1.5 bil lion) and because their illnesses varied in severity, The identical inherit ance would tend to rule out genetic differences as the cause of the neurops ychological differences; however, we cannot disentangle the effects of earl y brain injury and harsh punitive treatment as factors accounting for the d ifferences in the severity of their disorders. We conducted neuropsychologi cal examinations of the Genains at age 66, compared their test profiles, an d contrasted certain test scores at 66 with those at ages 27 and 51, Test r esults indicate generally stable (or even improved) performance over time a nd support the notion that cognitive decline is not a degenerative process in schizophrenia. The Genains remind us of the exquisite interaction among variables that must be understood before additional, satisfactory progress can be made in preventing the development and predicting the course of schi zophrenia.