Ukuthelekisa i-Trisomy, iTranslocation, kunye neifomu zikaMoses zesiXeko
Mhlawumbi uyazi ukuba i-Down syndrome yimizimba yezofuzo ezidala ubuninzi beempawu eziphathekayo kunye nokulibaziseka kokuphuhliswa. Emva koko, kuqhelekileyo: I-National Down Syndrome Society (NDSS) ichaza kwiwebsite yayo ukuba malunga nabantwana abangama-700 bazalwa benesimo.
Kodwa ngaba uyazi ukuba kukho iintlobo ezahlukeneyo ze-Down syndrome, zonke ezibandakanya i-chromosomes ye-21?
Uhlobo oluqhelekileyo, i- trisomy 21 , lujongene neepesenti ezingama-95 zeengxaki ze-Down syndrome. Phantse iipesenti ezine zibizwa ngokuba yi-translocation Down syndrome, kunye nepesenti enye eseleyo, i-mosaicism. Nantsi ingqwalaselo emfutshane malunga nendlela ezi ntlobo ezintathu ze-Down syndrome.
Trisomy 21 Down Syndrome
Ngokuqhelekileyo abantu bazuze iimbini ze- chromosomes ezingama-23 ezivela kumabini kunye nonina kangangokuba zizonke ezingama-46. Noko ke, abantu abane-trisomy Down syndrome bavutha ngama-chromosomes angama-47 kuba bafumana ikopi eyongezelelweyo ye-chromosome 21. Oku kwenzeka xa i-chromosomes ukusuka kwiqanda okanye i-sperm ayihluleki.
Ukutshintshiswa kweSystem Syndrome
I-Translocation Down syndrome iyenzeka xa ama-chromosomes amabini, enye yeyona nombolo 21, idibene ndawonye ekupheleni kwayo. Endaweni yokuzimela ezizimeleyo ezintathu, ama-chromosomes angama-21 ahlukeneyo, umntu ohambisa i- Down syndrome unama-kromosomes angama-21 adibeneyo kunye ne-chromosome ye-21 ehlanganiswe kwenye i-chromosome.
Ama-chromosomes axhunyiwe abizwa ngokuba ngama-chromosomes ezivela. Ngamanye amaxesha i-chromosome evela kumzuzwana izuze umzali, kodwa nayo inokwenzeka okokuqala ngqa kumntu one-Down syndrome. (Oku kwaziwa ngokuba ngu-no no translocation). Xa umntwana efunyaniswa ukuba unikwe i-Down syndrome, kubalulekile ukuba abazali bakhe bahlolwe i-karyotype ukubona ukuba omnye wabo uthatha ukudluliselwa, kuba isenokudluliselwa komnye umntwana.
Nangona ukuthunyelwa kwe-Down syndrome kwenzeka ngeendlela ezahlukeneyo kune-trisomy 21, izinto ezibonakalayo kunye nempawu eziphawula imeko ziyafana.
Mosaic Down Syndrome
Kwi- mosaic Down syndrome , akuzona zonke iiseli zomzimba ezine-chromosomes ezingama-46. Kunoko, ipesenti yeeseli zinama-chromosomes angama-47, kunye nekopi eyongezelelweyo ye-chromosome 21.
Ngokomzekelo, kwisampuli yeeseli zegazi ezingama-20 ukusuka kwintsana ene-mosaic Down syndrome, iiseli ezili-10 zingenayo i-chromosome engaphezulu kwama-21 (ama-47 ama-chromosomes iyonke) ngelixa elinye lala maseli alikho. Ngokusekelwe kwezi zinto zibalwa, umntwana uya kuba ne-mosaicism ye-50 ekhulwini. Ukuba le sampula yegazi yayimele i-blood ngokubanzi, ihafu yeseli kwigazi lomntwana yayiqhelekileyo, kwaye esinye isiqingatha singaba ne-chromosome eyongezelelweyo.
Umgangatho womntu wobugqwetha uhluke ngokusekelwe kwisampuli yamathambo. Ngokomzekelo, isampuli yesikhumba ingabonisa indlela eyahlukileyo yokubonakalisa i-mosaic ukususela kwisampula yeengcubu zomzimba ezivela kumntu ofanayo. Kwimeko nayiphi na into, abantu abanomdla ngokuqhelekileyo bahlala bengenazo iimpawu eziphathekayo kunye nezinye iimpawu, nangona kunjalo nabani na, akunakwenzeka ukwenza uhlaka olubanzi.