Genetiese argitektuur van skisofrenie : wat weet en sê ons nou?

Abstract

AFRIKAANS : Tien jaar gelede is bevindinge oor die genetiese argitektuur van skisofrenie en die bydrae van studies onder Afrikaners gerapporteer. In hierdie oorsigsartikel word gekyk na wat ons nou weet en watter inligting ons aan pasiënte en familie kan oordra. Genetiese oorvleueling by psigiatriese steurnisse word uitgelig. Daar word beklemtoon dat die kliniese gebruik van poligeniese risikotellings (PRT) vir skisofrenie tentatief is. Daar word ook verwys na die nut van die uitsonderlike gebruik van PRT in kombinasie met kopiegetalvariante-toetsing (KGV-toetsing) word genoem. Tydens genetiese raadgewing vir skisofrenie word pasiëntgesentreerde psigoterapeutiese benadering gevolg. In hierdie proses word die pasiënt bemagtig om leefstylveranderinge aan te bring wat onder andere omgewingsrisikofaktore die hoof sal bied. Skisofrenie is poligeniese steurnis, waar die kumulatiewe eff ek van verskeie gene wat onafhanklik reageer tot die uiteindelike eff ek lei. Daar is tans geen genetiese toets beskikbaar om diagnose van skisofrenie te bevestig nie. Die individuele voorspelling van risiko om skisofrenie te ontwikkel bly uitdaging. Algemene en seldsame DNAvariante betrokke by skisofrenie word gebruik om die komplekse aard van die siektepatogenese te verduidelik. Epigenetika in genetiese raadgewing word beklemtoon. Hopelik sal hierdie inligting die onrealistiese verwagtinge, stigma en diskriminasie teenwerk wat met onvoldoende begrip van genetiese bevindinge in skisofrenie verband hou.ENGLISH : Ten years ago findings on the genetic architecture of schizophrenia and the contribution of findings in Afrikaners were reported. In this review article the latest findings on this topic are discussed, as well as the information that we can now communicate to patients and family members. Genetic overlap among psychiatric illnesses is highlighted. It is emphasised that polygenic risk scores (PRS) for schizophrenia is tentative in clinical practice. The rare use of PRS in combination with copy number variant (CNV) testing is also referred to. During genetic counselling for schizophrenia a patient-centred psychotherapeutic approach is followed. In this process the patient is empowered to make lifestyle changes that will address environmental risk factors, inter alia. Schizophrenia is a polygenic disorder, where the cumulative effect of several genes reacting independently will lead to the end result. At present there is no genetic test available to confirm a diagnosis of schizophrenia. The individual prediction of risk to develop schizophrenia remains a challenge. Common and rare DNA variants involved in schizophrenia are used to explain the complex nature of the pathogenesis of illness. Epigenetics in genetic counselling is emphasised. Hopefully this information will help to combat unrealistic expectations, stigma and discrimination related to misunderstanding of the genetic findings in schizophrenia.