Robertsonian translocations: piav qhia, nta thiab cov yam ntxwv ntawm

Tag nrho volume ntawm kev tshuaj ntsuam genetic khoom siv nyob rau hauv tag nrho cov 46 officers ntawm chromosomes. Ib tug chromosome yog lub npe hu los ntawm biology, pom nyob rau hauv lub cell nucleus. Ib tug noj qab nyob zoo neeg muaj ib tug karyotype ntawm 23 officers ntawm diploid chromosomes. Qhov ntawd yog 46 XX - chromosome teem cov poj niam thiab 46 XY - txiv neej txheej chromosomes. Thaum koj ua txhaum ib yam ntawm cov chromosome, qhov yooj yim "uas hnov" ntawm lub caj code, ntau hom ntawm kev ua txhaum tshwm sim.

Change yog tsis cim rau tib neeg. Me hloov nyob rau hauv kev tshuaj ntsuam genetic khoom pab mus rau ntau haiv neeg ntawm ces ntawm qhov. Nyob rau hauv lub thiaj li hu ua kuas chromosomal translocation hloov tshwm sim tsis muaj ib tug tsis ntawm cov ntaub ntawv thiab tsis pub luam. Feem ntau cov feem ntau qhov no tshwm sim thaum lub sij hawm meiosis (chromosome division), nyob rau hauv tas li ntawd, tej zaum ib feem ntawm lub chromosomes yog duplicated (Individuals tshwm sim), thiab ces lub txim yog unpredictable. Tiam sis peb yuav xav txog xwb Robertsonian translocations, lawv tus yam ntxwv thiab los.

Robertsonian translocation - yog dab tsi? Caj teeb meem ntawm noob neej

Vim kev sib tawg ntawm lub chromosome nyob ze ntawm lub centromere muaj structural kev hloov nyob rau hauv tus tib neeg lub caj code. Cov kis tej zaum yuav muaj ib zaug xwb, tab sis nws tshwm sim dua. Ib sab caj npab ntawm chromosome tom qab tus so (feem ntau yog luv luv caj npab) yog poob lawm. Tab sis tuaj nyob rau mob qhov twg so tshwm sim ib txhij nyob rau hauv 2 chromosomes, luv luv caj npab uas yog swapped. Tej zaum, lawv yog cov yuav raug translocation tsuas qhov chaw ntawm lub xub pwg. Tab sis xws li luv luv caj npab ntawm acrocentric chromosomes nyob rau hauv lub hom (nyob qhov twg lub centromere cais lub chromosome rau ib tug ntev thiab luv luv caj npab) yeej tsis nqa tseem ceeb heev cov ntaub ntawv. Dhau li ntawm tus tsis xws lub ntsiab yog tsis yog li ntawd ib qho tseem ceeb vim hais tias cov roj ntsha khoom no theej rau lwm cov acrocentric chromosomes.

Tab sis thaum sib cais hauv lub luv luv caj npab fused nrog luv luv caj npab ntawm lwm noob, thiab tshuav ntev kuj soldered mus rau txhua lwm yam, xws li ib tug translocation yog tsis balanced. Xws "rearrangement" kev tshuaj ntsuam genetic khoom - qhov no yog ib tug Robertsonian translocation.

Kuv researched thiab piav no hom ntawm translocation W. Robertson nyob rau hauv 1916. Thiab nws lub npe twb hu ua thiab ib tug anomaly. Robertsonian translocation yuav ua tau kom txoj kev loj hlob ntawm cov qog nqaij hlav, tab sis tej zaum yuav tsis muaj kev cuam tshuam cov tsos thiab noj qab haus huv ntawm cov cab kuj. Txawm li cas los, tus me nyuam nyob rau hauv Feem ntau, yog ib tug niam txiv muaj lub translocation, yug muaj kev tsis taus.

Ntau npaum li cas hloov?

Vim kev txhim kho nyob rau hauv technology thiab cov kev loj hlob ntawm noob caj noob ces raws li ib tug science, niaj hnub no nws yog tau paub nyob rau hauv ua ntej yog hais tias muaj yog kev txawv txav nyob rau hauv lub karyotype ntawm lub hauv plab me nyuam. Nws yog tam sim no tau mus nqa tawm cov txheeb cais: yuav ua li cas feem ntau muaj cov kev tshuaj ntsuam genetic anomaly? Raws li tam sim no cov ntaub ntawv, Robertsonian translocations tshwm sim nyob rau hauv ib tug ntawm ib txhiab me nyuam mos. Feem ntau cov feem ntau thiaj paub hais tias translocation ntawm chromosome 21.

Me chromosomal translocation yog kiag li tsis muaj kev hem thawj rau nws cov neeg uas hnov. Tab sis thaum nws muaj feem xyuam rau ib qho tseem ceeb hais txog qhov code, tus me nyuam tej zaum yuav yug tuag los yog tuag nyob rau hauv ib ob peb lub hlis, xws li, piv txwv li, cov ntaub ntawv nrog lub syndrome Patau. Tab sis Patau syndrome tshwm sim heev tsis tshua muaj. Qhov chaw 1 nyob rau hauv 15,000 yug.

Yam pab mus rau lub rov tshwm sim ntawm ib tug translocation nyob rau hauv chromosomes

Nyob rau hauv cov xwm, muaj tshwm sim hloov, ie, unprovoked. Tab sis cov ib puag ncig ua rau nws tus kheej kev kho me ntsis rau txoj kev loj hlob ntawm genome. Ob peb yam tseem ceeb pab txhawb kom muaj ntau heev mutational hloov. Tej yam zoo yog hu ua mutagenic. Paub los ntawm yam nram qab no:

• kev cuam tshuam nitrogenous bases;
• alien DNA biopolymers;
• naim li haus dej haus cawv kom tsawg thaum lub sij hawm cev xeeb tub;
• tej yam kab mob thaum lub sij hawm cev xeeb tub.

Cov feem ntau translocation tshwm sim vim qhov teeb meem los ntawm hluav taws xob nyob rau hauv lub cev. Nws muaj feem xyuam rau ultraviolet hluav taws xob, protons thiab X-rays, thiab gamma rays.

Uas yog yuav hloov chromosome?

Undergo translocation ntawm chromosome 13, 14, 15 thiab 21. Cov feem nrov thiab txaus ntshai translocation - ib tug Robertsonian translocation ntawm chromosomes 14 thiab 21.

Yog hais tias raws li ib tug tshwm sim ntawm meiosis ntaub ntawv ntxiv chromosome (trisomy) me nyuam hauv plab nrog xws li translocation, tus me nyuam yuav yug los nrog Down syndrome. Cov tib cov ntaub ntawv yog sai tau yog tias Robertsonian translocation tau tshwm sim ntawm chromosomes 15 thiab 21.

Translocation ntawm chromosome band D

Robertsonian translocation chromosome Group D muaj feem xyuam rau xwb acrocentric chromosomes. Chromosomes 13 thiab 14 yog muab kev koom tes nyob rau hauv translocations nyob rau hauv 74% ntawm cov neeg, thiab lawv yog hu ua kauj translocations, uas yog feem ntau txaus ntshai lub txim rau lub neej tsis muaj.

Txawm li cas los, muaj ib tug teeb meem uas tej zaum yuav nrog xws anomalies. Robertsonian translocation 13, 14 nyob rau hauv cov txiv neej yuav ua tau kom tsis hnov fertility ntawm cov txiv neej cov cab kuj (45 xy chromosome set). Vim lub fact tias, vim txoj kev poob ntawm ob luv luv caj npab es tsis txhob ntawm 2 officers ntawm chromosomes feem ntau muaj yog tsuas yog ib tug uas muaj ob tug ntev, gametes xws li ib tug txiv neej tsis tau muab ib tug zaum offspring.

Cov tib Robertsonian translocation 13, 14 nyob rau hauv cov poj niam thiab thiaj li nws muaj peev xwm muaj ib tug me nyuam. Hli muaj xws li cov poj niam, thiab tsis tau muaj lub sij hawm thaum lawv yug me nyuam kom noj qab nyob cov me nyuam. Tab sis cov txheeb cais tseem qhia hais tias nws yog tsis tshua muaj. Yeej, lawv cov me nyuam yog tsis zaum.

Lub txim ntawm translocations

Peb tau pom tias ib txhia cov yam ntxwv hloov yog heev qub thiab tsis hem. Robertsonian translocation chav tsev yog txiav txim los ntawm tus tsom xam. Tab sis lub re-translocation nyob rau hauv lub teeb ntawm cov tiam tom ntej ntawm chromosomes twb txaus ntshai.

Robertsonian translocation 15 thiab 21 nyob rau hauv nrog lwm yam ntxwv hloov tej zaum yuav txawm yuav disastrous. Tag nrho cov txim ntawm tej yam ntxwv hloov nyob rau hauv lub karyotype piav nyob rau hauv kom meej. Nco qab tias lub karyotype - nws yog xam qhovkev rau hauv tus neeg txheej chromosomes nyob rau hauv lub nucleus.

Trisomy thiab translocation

Tsis tas li ntawd translocations noob caj noob ces cais abnormality xws li ib tug trisomy chromosome. Trisomy txhais tau tias me nyuam hauv plab karyotype tau teem ib tug ntawm triploid chromosomes es tsis txhob ntawm lub 2 luam tej zaum tshwm sim mosaic trisomy. Qhov ntawd yog triploid txheej cai tsis nyob rau hauv tag nrho cov hlwb ntawm lub cev.

Trisomy ua ke nrog Robertsonian translocation ua rau mob loj heev txim: xws li Patau syndrome, Edwards thiab ntau Down syndrome. Nyob rau hauv tej rooj plaub, lub teeb ntawm anomalies ua rau tus menyuam nchuav nyob rau hauv thaum ntxov ua sawv.

Down syndrome. ces

Nws yuav tsum tau muab sau tseg tias translocation uas chromosomes 21 thiab 22 yog ruaj khov. Tej anomalies yog tsis tuag, yog tsis ib nrab-tuag, tab sis tsuas yog ua rau txoj kev loj hlob tsis taus. Yog li, trisomy 21 nyob rau hauv ua ke nrog nrog ib tug Robertsonian translocation nyob rau hauv lub karyotype nyob rau hauv lub tsom xam ntawm me nyuam hauv plab karyotype - Nco ntsoov "kos npe rau" ntawm Down syndrome, ib tug kev tshuaj ntsuam genetic tus kab mob.

Down syndrome yog yus muaj los ntawm ob lub cev thiab kev puas hlwb kev tsis taus. Twv ua ntej ntawm lub neej ntawm cov neeg no yog dej siab. Txawm tias lub plawv kab mob thiab ib co physiological kev hloov nyob rau hauv lub cev pob txha, thiab lawv lub cev yog ua tau hauj lwm li qub.

Cov yam ntxwv nta ntawm lub syndrome:

• ca lub ntsej muag;
• enlarged tus nplaig;
• ib tug ntau ntawm daim tawv nqaij nyob rau hauv lub caj dab, mus rau quav;
• clinodactyly (curvature ntawm cov ntiv tes);
• epicanthus;
• kab mob plawv yog tau nyob rau hauv 40% ntawm cov neeg.

Cov neeg uas muaj no syndrome maj mam pib mus, mus hais cov lus. Thiab kuj yuav kawm nws nyuaj tshaj lwm cov me nyuam ntawm cov tib lub hnub nyoog.

Tsis tau lawv muaj peev xwm ntawm cov chaw ua hauj lwm nyob rau hauv lub zej lub zos thiab nrog ib co kev pab txhawb thiab kom zoo ua hauj lwm nrog cov me nyuam lawv zoo socialized nyob rau hauv lub neej yav tom ntej.

Patau syndrome

Lub syndrome yog tsis tshua muaj heev tshaj Down syndrome, tab sis lub tsis xws luag ntawm ntau hom muaj xws li ib tug me nyuam heev npaum li cas. Yuav luag 80% ntawm cov me nyuam nrog rau qhov no mob tuag tsis pub dhau 1 xyoo ntawm lub hnub nyoog.

Nyob rau hauv 1960 nws kawm no anomaly thiab sab kev tshuaj ntsuam genetic ua rau tsis ua hauj lwm Klaus Patau, txawm hais tias nws nyob rau hauv 1657 piav txog tus syndrome T. Bartolini. Cov pheej hmoo ntawm cov mob yog nce nyob rau hauv cov poj niam uas muab yug tau ib tug me nyuam tom qab 31 xyoo.

Cov me nyuam no yog heev heev lub cev tsis xws luag ua ke uas muaj teebmeem psychomotor txoj kev loj hlob. Yam ntxwv ntawm lub syndrome:

• microcephaly;
• txawv txav ob txhais tes, feem ntau tsim nyob rau ntxiv ntiv taw;
• tsawg txheej pob ntseg lus zoo lawm;
• cleft di ncauj;
• luv luv caj dab;
• nqaim ob lub qhov muag;
• kom meej meej "sunken" choj;
• tsis xws luag ntawm ob lub raum thiab lub plawv;
• cleft di ncauj los yog palate;
• Cev xeeb tub muaj no tsuas muaj ib txoj hlab leeg.

Ib tug me me muaj pes tsawg tus ntawm tseem muaj sia nyob cov me nyuam mos kev pab kho mob. Thiab lawv yeej tseem nyob tau ib lub sij hawm ntev. Tab sis congenital anomalies tseem muaj kev cuam tshuam ntawm qhov xwm ntawm lub neej thiab nws cov brevity.

Edwards syndrome

Trisomy 18 chromosome translocation nyob rau hauv lub keeb kwm yav dhau ua rau Edwards Syndrome. Qhov no syndrome yog tsis tau paub zoo. Nrog rau qhov no mob ib tug me nyuam nyuam qhuav tseem muaj sia nyob rau lub hlis. natural xaiv txoj cai tsis pub kom loj hlob tshuam uas muaj ntau hom kev xiam oob qhab.

Nyob rau hauv dav dav, lub xov tooj ntawm txawv tsis xws luag nyob rau hauv lub syndrome Edwards - txog 150 yog tam sim no malformations cov hlab ntsha, lub plawv, hauv nruab nrog cev. Yuav tam sim no nyob rau hauv cov me nyuam mos hypoplasia ntawm lub cerebellum. Muaj anomalies ntawm cov qauv ntawm cov ntiv tes. Heev feem ntau xws li ib tug txawv anomaly tshwm raws li ib tug ko taw deformity.

Yuav ua li cas kev ntsuam xyuas seb puas txawv txav nyob rau hauv utero?

Rau karyotype tsom xam nyob rau hauv me nyuam hauv plab tsim nyog kom tau cov ntaub ntawv uas - me nyuam hauv plab lub hlwb.

Ob peb ntsuam. Ci ntsa iab yuav ua li cas nws tshwm sim.

1. chorionic villus zauv. Qhov tsom xam nyob rau hauv 10 lub lis piam. Cov villi - yog cov ncaj particle tsev me nyuam. Qhov no particle kev lom khoom yuav qhia txhua yam hais txog lub neej yav tom ntej ntawm lub txiv hmab txiv ntoo.

2. Amniocentesis. Nrog lub koob yog coj ib tug ob peb me nyuam hauv plab lub hlwb, thiab amniotic kua. Lawv yog npaum li cas feem ntau nyob ntawm lub lim tiam 16 uas cev xeeb tub, thiab tom qab ib tug ob peb lub lis piam, qhov ob peb yuav tau txais lub ncauj lus kom ntxaws txog tus me nyuam txoj kev noj qab haus huv.

Nyob rau qhov no tsom xam yuav muab xa mus rau niam nrog kev pheej hmoo ntawm delivering ib tug me nyuam muaj kev tsis taus zog. Feem ntau caj tsom qhia cov officers nyob rau hauv uas:

1) twb unexplainable abortions;

2) cov khub tau tsis tau xeeb tub ib tug me nyuam;

3) nyob rau hauv lub tsev neeg tau mus kawm lub zoo txog kev sib txuas lus xwm.

Cov tub hluas ntxhais hluas yuav muaj ib tug Robertsonian translocations ntawm ib co chromosomes. Thiab yog li ntawd lawv yuav tsum ua rau kom tus tsom xam rau ib tug karyotype paub dab tsi yog qhov uas yuav mus nqa thiab muab yug tau ib tug noj qab nyob zoo tus me nyuam.