Uvavanyo lweDNA oluSebenzayo ngaphambi koSana

Umxholo

• Yintoni uvavanyo lwe-DNA engekazalwa engeyiyo iselfowuni (cfDNA)?
• Isetyenziselwa ntoni?
• Kutheni le nto ndifuna ukuvavanywa kokubeleka kokubeleka kwe-cfDNA?
• Kwenzeka ntoni ngexesha lokuvavanywa kokubeleka kwe-cfDNA kokubeleka?
• Ngaba kuya kufuneka ndenze nantoni na ukulungiselela olu vavanyo?
• Ngaba bukhona ubungozi kuvavanyo?
• Zithetha ntoni iziphumo?
• Ngaba ikhona enye into endifuna ukuyazi malunga nokuvavanywa kokubeleka kwe-cfDNA kokubeleka?
• Izalathiso

Yintoni uvavanyo lwe-DNA engekazalwa engeyiyo iselfowuni (cfDNA)?

Ukuvavanywa kwegazi kwangaphambi kokubeleka kwe-DNA (cfDNA) kuvavanyo lwegazi kubafazi abakhulelweyo. Ngexesha lokukhulelwa, enye ye-DNA yosana olungekazalwa ijikeleza kwigazi likanina. Uvavanyo lwe-cfDNA lujonga le DNA ukufumanisa ukuba ngaba umntwana kunokwenzeka ukuba abe ne-Down syndrome okanye esinye isifo esibangelwa yi-trisomy.

I-trisomy kukuphazamiseka kwee-chromosomes. IiChromosomes ngamalungu eeseli zakho aqukethe imfuza yakho. Imfuza ngamalungu e-DNA agqithiselwe kumama notata wakho. Baphethe ulwazi olumisela iimpawu zakho ezizodwa, ezinjengokuphakama nombala wamehlo.

• Ngokwesiqhelo abantu banee-chromosomes ezingama-46, zahlulwe zangama-23 amabini, kwiseli nganye.
• Ukuba enye yezi zibini inekopi eyongezelelweyo ye-chromosome, ibizwa ngokuba yi-trisomy. I-trisomy ibangela utshintsho kwindlela umzimba kunye nengqondo ekhula ngayo.
• Kwi-Down syndrome, kukho ikopi eyongezelelweyo ye-chromosome 21. Oku kwaziwa ngokuba yi-trisomy 21. I-Down syndrome sisifo esixhaphake kakhulu kwi-chromosome eMelika.
• Ezinye iingxaki ze-trisomy zibandakanya i-Edwards syndrome (i-trisomy 18), apho kukho ikopi eyongezelelweyo ye-chromosome 18, kunye ne-Patau syndrome (i-trisomy 13), apho kukho ikopi eyongezelelweyo ye-chromosome 13. Ezi ngxaki zinqabile kodwa zinzulu kune-Down syndrome. Uninzi lweentsana ezine-trisomy 18 okanye i-trisomy 13 ziyafa kunyaka wokuqala wobomi.

Ukuhlolwa kwe-cfDNA kunomngcipheko omncinci kuwe nakumntwana wakho, kodwa akunakuxelela ngokuqinisekileyo ukuba umntwana wakho unesifo se-chromosome. Umboneleli wakho wokhathalelo lwempilo uyakufuna uku-odola ezinye iimvavanyo ukuqinisekisa okanye ukukhupha isifo.

Amanye amagama: i-DNA yesibeleko engenaseli, i-cffDNA, uvavanyo olungenasiphelo lwangaphambi kokubeleka, i-NIPT

Isetyenziselwa ntoni?

Ukuhlolwa kwe-cfDNA kuhlala kusetyenziswa ukubonisa ukuba umntwana wakho ongekazalwa unobungozi obonyukayo kwesinye sezi ngxaki zilandelayo ze-chromosome:

• I-Down syndrome (i-trisomy 21)
• Isifo sikaEdwards (trisomy 18)
• IPatau syndrome (trisomy 13)

Uvavanyo lunokusetyenziselwa:

• Misela isini somntwana (isini). Oku kunokwenziwa ukuba i-ultrasound ibonisa ukuba amalungu esini omntwana akabonakali ngokucacileyo ukuba yindoda okanye ibhinqa. Oku kunokubangelwa kukuphazamiseka kwee-chromosomes zesini.
• Jonga uhlobo lwegazi lweRh. I-Rh yiprotein efumaneka kwiiseli ezibomvu zegazi. Ukuba unayo iprotheni, uthathwa njenge-Rh positive. Ukuba awunayo, awunayo i-Rh. Ukuba awunayo i-Rh kwaye umntwana wakho ongekazalwa une-Rh, amajoni omzimba wakho anokuhlasela iiseli zegazi lomntwana wakho. Ukuba ufumanisa ukuba awunayo i-Rh ekuqaleni kokukhulelwa, ungathatha amayeza ukukhusela umntwana wakho kwiingxaki ezinobungozi.

Ukuhlolwa kwe-cfDNA kunokwenziwa kwangoko kwiveki yeshumi yokukhulelwa.

Kutheni le nto ndifuna ukuvavanywa kokubeleka kokubeleka kwe-cfDNA?

Ababoneleli abaninzi bezempilo bancomela oku kuhlolisiswa kwabasetyhini abakhulelweyo abasengozini enkulu yokuba nomntwana onesifo se-chromosome. Unokuba semngciphekweni omkhulu ukuba:

• Uneminyaka engama-35 okanye ngaphezulu. Ubudala bukamama ngowona mngcipheko uphambili wokuba nomntwana one-Down syndrome okanye ezinye iingxaki zetrisomy. Umngcipheko uyanda njengokuba umfazi esiya esiba mdala.
• Unomnye umntwana onesifo se chromosome.
• I-ultrasound yakho yomntwana ayizange ibonakale iqhelekileyo.
• Ezinye iziphumo zovavanyo lokubeleka zazingaqhelekanga.

Abanye ababoneleli ngezempilo bacebisa ukuhlolwa kwabo bonke abasetyhini abakhulelweyo. Kungenxa yokuba uhlolo alunabungozi kwaye lunezinga eliphezulu lokuchaneka xa kuthelekiswa nolunye uvavanyo lokuvavanywa kokubeleka.

Wena nomboneleli wakho wezempilo kufuneka nixoxe ukuba ngaba ukuhlolwa kwe-cfDNA kukulungele.

Kwenzeka ntoni ngexesha lokuvavanywa kokubeleka kwe-cfDNA kokubeleka?

Ingcali yokhathalelo lwempilo iyakuthatha isampulu yegazi kumthambo engalweni yakho, isebenzisa inaliti encinci. Emva kokuba inaliti ifakiwe, inani elincinci legazi liya kuqokelelwa kwityhubhu yovavanyo okanye igutyana. Unokuziva uluma kancinci xa inaliti ingena okanye iphuma. Oku kuhlala kuthatha imizuzu engaphantsi kwesihlanu.

Ngaba kuya kufuneka ndenze nantoni na ukulungiselela olu vavanyo?

Unokufuna ukuthetha nomcebisi wezofuzo ngaphambi kokuba uvavanywe. Umcebisi ngemfuzo yingcali eqeqeshwe ngokukodwa kwimfuzo novavanyo lwemfuzo. Unokuchaza iziphumo ezinokubakho kunye nokuba zinokuthetha ntoni kuwe nakumntwana wakho.

Ngaba bukhona ubungozi kuvavanyo?

Akukho bungozi kumntwana wakho ongekazalwa kwaye mncinci kakhulu kuwe. Unokuba nentlungu encinci okanye ukrakra kwindawo apho inaliti yafakwa khona, kodwa uninzi lweempawu zihamba ngokukhawuleza.

Zithetha ntoni iziphumo?

Ukuba iziphumo zakho bezingalunganga, akunakulindeleka ukuba umntwana wakho abe ne-Down syndrome okanye esinye isifo se-trisomy. Ukuba iziphumo zakho bezikho, oko kuthetha ukuba kukho umngcipheko okhulayo wokuba umntwana wakho abe nenye yezi ngxaki. Kodwa ayinakuxelela ngokuqinisekileyo ukuba umntwana wakho uyachaphazeleka. Ukufumana isifo esiqinisekisiweyo ngakumbi uyakufuna ezinye iimvavanyo, ezinje nge-amniocentesis kunye ne-chorionic villus sampling (CVS). Ezi mvavanyo zihlala zikhuselekile, kodwa zinomngcipheko omncinci wokubangela ukuphuphuma kwesisu.

Ukuba unemibuzo malunga neziphumo zakho, thetha nomboneleli wakho wezempilo kunye / okanye umcebisi wezofuzo.

Funda ngakumbi malunga novavanyo lwelabhoratri, uluhlu lweereferensi, kunye neziphumo zokuqonda.

Ngaba ikhona enye into endifuna ukuyazi malunga nokuvavanywa kokubeleka kwe-cfDNA kokubeleka?

Ukuvavanywa kwe-cfDNA akuchanekanga kubafazi abakhulelweyo ngaphezulu kosana olunye (amawele, amawele amathathu, okanye nangaphezulu).

Izalathiso

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Ulwazi olukule ndawo akufuneki lusetyenziswe endaweni yonyango okanye iingcebiso. Nxibelelana nomboneleli wezempilo ukuba unemibuzo malunga nempilo yakho.