Having children when the parents are blood relatives

Transcription

1 Hving children when the prents re blood reltives When prents re blood reltives, there is higher risk of disese nd birth defects, stillbirths, infnt mortlity nd shorter life expectncy; Informtion bout heredity nd the risk of disese nd birth defects

2 The vst mjority of children born in Norwy re helthy, but ech yer, some children re born with serious diseses or birth defects. The closer the kinship between the prents, the higher the risk. If prents re blood reltives, for exmple, first cousins, the risk of hving children with diseses nd birth defects is twice s high s when the prents re not relted. The risk is lso higher if there re mny mrriges between blood reltives in the fmily, so tht the mn nd the womn re relted to ech other in severl wys. Close kinship between prents lso increses the risk of stillbirths (deth in mother s womb fter the 20th week of pregnncy) nd infnt mortlity (deth in the first yer of life), nd shortens life expectncy (deth t ll ges up to dulthood). There re mny resons why children re born with diseses nd birth defects. In some cses, the resons re in the genes we inherit from our prents. We ll crry genetic defects tht cn led to diseses in ourselves or in our children. Usully this does not hppen becuse we hve two copies of every gene. If the one fils to work becuse of defect, the other cn usully do the job. Both the mother nd the fther cn hve one or more genes tht cn led to disese without being ill themselves, nd without ny of their children being ill. For their children to get the disese, they hve to inherit defect in the sme gene from both prents. The risk tht the mother nd the fther both hve the sme genetic defect nd tht it will result in disese is usully smll, but it increses when prents re blood reltives. This is becuse both my hve inherited the sme genetic defect from their common ncestors. WHT CONDITIONS RE WE TLKING BOUT? Not ll diseses nd bnormlities re inherited. However, reserch indictes tht the risk of hving child with birth defects nd certin hereditry diseses increses if prents re close reltives. Conditions inherited due to kinship re often serious. Such conditions include metbolic diseses, skin diseses nd blood diseses, physicl nd mentl development problems, s well s problems with hering nd/or vision. These conditions often entil high risk of repetition, tht is, severl children in the sme fmily cn inherit the disese. When mother nd fther hve defect in the sme gene, there is 25 per cent chnce tht their offspring will be born with tht prticulr disese or deformity. The risk is the sme for ech pregnncy. Some conditions cn led to stillbirths, infnt mortlity nd shorter life expectncy. Close kinship between prents lso increses the risk of other birth defects, lthough it is not known why. It is nonetheless importnt to ber in mind tht the overll risk of hving children with severe congenitl (inherited) conditions is smll.

3 WHT CN YOU DO? If you re blood reltives nd you hve hd one or more children with debilitting disese or birth defect, or if you know of someone in your fmily who hs such problems, you will be offered genetic counselling before ny (new) pregnncy. You cn lso receive genetic counselling if you re plnning to hve child nd wonder whether you hve n incresed risk of hving children with hereditry diseses or congenitl birth defects. Your fmily doctor cn refer you to genetic counselling, which is offered t the lrgest hospitls in Norwy. WHT IS GENETIC COUNSELLING? Genetic counselling involves consulttion with helth cre professionl who explins how diseses re pssed down from prents to children nd why the risk of hving children with different diseses increses when prents re blood reltives. Genetic counsellors cn lso give prents informtion bout wht genetic work-ups entil, nd wht the work-ups cn nd cnnot identify. TINY DOSE OF THEORY The body is mde up of cells. The cells contin genetic mteril (DN) tht is pssed on from prents to children. DN consists of thousnds of different genes. Genes help decide how the body works. People inherit one set of ll the genes from their mother nd one set from their fther. Since they hve mutul ncestors, reltives hve mny genes tht re identicl. This drwing shows how genes re trnsferred from prents to child ren. In this cse, the mother nd the fther hve defect in the sme gene. The gene defect my result in disese, but since prent hs one gene without defect nd one with defect, he or she is helthy. These genes cn be trnsferred from prents to children in four different wys. child who hs the combintion - hs not inherited the genetic defect, nd will not get the disese. The two children who hve the combintion - nd - hve inherited the genetic defect from one of their prents. The children re helthy, but like their mother nd fther, they hve genetic defect tht they cn pss on to their children. child with the combintion - hs inherited genetic defect from both prents, mening this child will get the disese. The child cn be born with the disese or develop it lter in life. Fther C Clinicl Tool, Inc. Mother consulttion does not imply ny commitment nd does not necessrily involve exmintions or tests. During the consulttion, the counsellor will sk bout the fmily s medicl history. n evlution cn then be mde to determine the risk of giving birth to child with disese. During the consulttion, you cn lso discuss wht you cn do if you hve child/re expecting child with hereditry disese, whether the disese cn be treted nd who might be ble to help the child nd the fmily. Genetic counselling lso includes informtion bout the possibilities for screening nd exmintions for the mn, the womn, the foetus, nd ny children nd other fmily members. SCREENING ND EXMINTIONS If the genetic defect tht results in disese in the fmily is known, gene test cn determine whether or not n individul crries the defective gene. Even if there re cses of the disese in the fmily, the gene defects tht cuse diseses or birth defects re not lwys known. If the genetic defect tht cuses disese in the fmily is known, pregnnt womn cn be offered genetic foetl dignostics, for exmple by performing genetic test on the plcent. If there is risk of congenitl birth defects, specil ultrsound techniques cn be used to exmine the foetus. The possibilities for screening nd exmining foetuses, children nd dults will be discussed during the genetic counselling session. Gene tests re only offered if there is known disese in the fmily.

4 P R C T I C L I N F O R M T I O N list of fmily doctors is vilble from NV Helsetjenesteforvltning, telephone or on the Internet: Pregnnt women cn get pre-ntl check-ups with midwife, t public helth centre or from their fmily doctor. ll prentl check-ups orgnised by the municiplity re free of chrge. Trvel expenses The doctor or in connection with helth cre personnel will rrnge for pre-ntl checkups, genetic counselling or other they feel it is neces- n interpreter if exmintions nd sry nd/or you tretment cn be would like one. The covered under the municiplity or the regultions lid hospitl will cover down in the ct the cost of n relting to Ptients interpreter. Rights. For more detiled informtion, see: For more informtion bout the rights of prents who hve children with disbilities, plese check with the Socil Services office t the hospitl, public helth centre or the locl NV office. Informtion is lso vilble from Norwegin Federtion of Orgnistions of Disbled People If you hve questions bout your child s dignosis or you seek contct with other fmilies tht hve children with rre hereditry dignosis, ring free of chrge to the Directorte of Helth s Public Service telephone ( ). (FFO) Rights Centre, telephone (+47) Relevnt websites Relevnt informtion from the Directorte of Helth: Informtion pmphlet «Children nd young people with diminished functionl bilities Wht rights do the fmily hve?» (IS-1298) Informtion for pregnnt women on foetl dignostics (IS-1313) Both pmphlets re vilble from the Directorte of Helth s Printing Office (telephone no ).

5 When prents re blood reltives, there is higher risk of disese nd birth defects, stillbirths, infnt mortlity nd shorter life expectncy. To hve child with severe diseses nd disorders my cuse hevy strin for the fmily in question. IS-1611 E