Genetics and the mystery of Schizophrenia What lies ahead Author Mustafa Abbas Genomics Bioinformatics and medicine Biochem 118Q Spring 2002 Professor Douglas Brutlag The Family Illness I had so many reasons not to think about schizophrenia about the terror it caused me as a child When I was six I watched my brilliant brother change from an engaging 16 yearold to a zombie who stared into space for hours Two years later I saw my older sister turn cruel and loud screaming for what seemed like hours I was too young to know anything about schizophrenia but I knew something was terribly wrong Like many with this disease neither my brother or sister could find satisfactory treatment resulting in my brother s leaping off a cliff to his death and in the regular recurrence of my sister s psychotic rages Schizophrenia isn t the multiple personality of movie stereotype but it is a horrible mental illness causing aural hallucinations and provoking paranoid delusions that can make peculiar behavior seem normal to the sufferer It often can be treated but it isn t yet curable And although public awareness of mental illness has come a long way in my lifetime it s difficult not to feel cursed by the shadows it casts For much of my life I have tried to believe that the madness was behind me After all my brother committed suicide 15 years ago while I was still in college and I ve been out of touch with my sister for close to 20 years They no longer inhabit my present life but their illnesses haunt me like ghosts At this point in my life that ghost has taken on a terrifying new shape It haunts me now with the question Would I have a child with schizophrenia Talking with geneticists did not dispel my fears in fact I soon learned that any children of mine would indeed have an increased risk of developing the illness that destroyed my siblings lives Although my fianc has no relatives with schizophrenia our kids would be as much as eight times more likely than the average person to have schizophrenia But even for my children schizophrenia is not a huge risk their chances range from 3 to 8 percent In the general population schizophrenia occurs in one out of every hundred people Several scientists told me that other considerations such as the fact that both my siblings had schizophrenia may increase the odds Another factor could be the severity of my sibling s cases Both became wildly uncontrollably ill These odds are all the scientists can offer me Unlike some other hereditary diseases the genes for schizophrenia have not yet been isolated there is no test All we can provide are our family histories all we can get in return are percentages If only the science were further along Still we try desperately to read our futures in the little information we have The genetics of mental illness will be much better understood in 20 years scientist say but there isn t much chance of current research having practical applications within the next five years when it would be useful to me In the end I have to face the fact that no one can tell me whether a child of mine would be healthy or ill And so the dilemma remains particularly for people like me who carry the memories of our siblings at the same time that we feel the pressure of encroaching age We cannot wait for research to provide the answers We must make our peace and our decisions with the knowledge at hand Clea Simon is an editor at the Boston Globe This piece is adapted from her recently released book Mad House Growing Up in the Shadow of Mentally Ill Siblings Doubleday portions of which appeared in The Washington Post Schizophrenia SZ is perhaps the most debilitating and tragic mental illness known It leads to a complete breakdown of personality and for many of its sufferers is a life sentence without hope of parole It effects at least 1 of the population worldwide regardless of race gender and economic condition Symptoms usually develop during young adulthood and continue to haunt its sufferers for their lifetime Positive symptoms include delusions hallucinations and disordered thought while the negative symptoms are social withdrawal and emotional flattening Complete recovery from the psychotic and emotional symptoms is very rare Unfortunately the illness is also perhaps the most elusive and mysterious among the mental afflictions in terms of its molecular environmental and genetic etiology Moreover the symptoms manifest themselves in such varying degrees of qualitative and quantitative intensity that it very hard to define a specific set of symptoms and behaviors associated with SZ Some researchers even suggest a mental health continuum from depression to bipolar depression to schizophrenia and varying intensity within its symptoms rather than looking at the illness as a discretely defined entity There is presently no biological test that can confirm the presence of the illness Schizophrenia is a complex multifactor disorder and like other multifactor disorders such as cancer does not follow classical mendelian inheritance patterns The genetics of Schizophrenia lika almost every mental disorder are indeed very complex Twin and family studies have revealed however that there is indeed a genetic component to the development of predisposition and finally to the manifestation of positive and negative symptoms of SZ Therefore families with one ill member have a greater chance of developing this illness later on It has been hypothesized by many researchers that 60 of the factors that give rise to Schizophrenia may be related to genetic susceptibility However researchers have not yet been able to identify a single predominant SZ gene This is complicated by studies that show that there is infact no single gene but a combination of genes acting with small effect to lead to the development of predisposition and pathology and the more genes necessary for the disorder the harder it is to detect any one of them Furthermore there is evidence that environmental factors interact with genetic predisposition in subtle ways for this inherited susceptibility to actually develop into a full blown Schizophrenic psychosis The nature of these non genetic effects is yet another mystery that futher complicates the search for distinct causal factors There is great hope however that by locating genes that are central to the development of familial predisposition to SZ we will get clues to many other nongenetic factors that play a central role in this disorder Let us look at the
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