Isizwe ngasinye eMhlabeni sinombala ovelele wezinwele, isikhumba namehlo. Isibonelo: phakathi kwabakhileyo eLatin America, abantu abangu-80-85%, i-Ukraine neRussia - 50% no-30% - kungatholakala amehlo aluhlaza. Umnyama waba isikhumba sabazali, amathuba okubukeka kwamehlo ensundu namnyama.
Amathuba ombala weso enganeni
Ngokuvamile umbala wamehlo wabazali nezingane uvumelana, kodwa kukhona okuhlukile. Amaqiniso anjalo achazwa yizinto ezihlukahlukene ze-melanin - i-pigment ehlose ukubala umbala, izinwele kanye ne-iris. Kubantu abanamahloni nabangaboni, i-pigment incane kakhulu, ayikho i-albinos nhlobo. Umbala obomvu wamehlo yizitsha zegazi, ezingasetshenziswanga ngombala. Kungani umbala omnyama we-iris ovame kakhulu? I-Genetics iphakamisa ukuthi amehlo aluhlaza ayingxenye ephawulekayo, eluhlaza okwesibhakabhaka neyimpunga. Ngakho-ke, kubazali abanamabala aluhlaza okwesibhakabhaka, umbala weso lomntwana ungabomvu, futhi kumama omama-grey nabama-daddies, izinyane elinamehlo amnyama azikwazi ukuzalwa.
Umuntu angachaza kanjani ukuthi umbala wamehlo wengane esanda kuzalwa usuhlale ufana njalo? Lokhu kungenxa yomsebenzi wamaseli e-melanocyte. Izisebenzi ezincane aziqali ngokushesha ukukhiqiza i-melanin. Kancane kancane ukuqoqa, i-pigment iyaphazamisa iris yamehlo kumbala ohlotshwe ngokofuzo. Kwezinye izingane i-turbidity iqala ukukhuphuka, futhi ngomnyaka wesigamu ingane ibukeka emhlabeni ngamehlo aluhlaza okwesibhakabhaka. Kwabanye, ngokuphambene nalokho, banomnyama. Khumbula ukuthi amehlo omntwana angakwazi ukumnyama ngesikhatsi. Kodwa ushintshe umbala omnyama obomvu ube yi-gray noma blue - ungalokothi. Okuhlukile kungasebenzi kahle emsebenzini we-melanocytes.
Ukuphulwa okunjalo kwenqubo yokwenza i-pigment akuvamile, futhi kufanele uqaphele abazali. I-Heterochromia - uma iso linye linemibala engaphezu kweyesibili, lingagcwele (iso lonke) noma ingxenye (ingxenye noma umkhakha we-iris). Ngezinye izikhathi umuntu uhlala nombala wamehlo ehlukile impilo yakhe yonke, ezwa ekhululekile, kodwa amacala uma ukwephulwa okunjalo kuphela nge-cataracts akuvamile. Ngakho-ke, abazali abaye baqaphela ukungaziphathi kahle kwamehlo wengane yabo kufanele babonise ngokushesha i-ophthalmologist.
Izingane zishintsha nini umbala wamehlo?
Ezinyangeni ezintathu zokuqala emva kokuzalwa, ushintsho embala we-iris akufanele kulindeleke. Ngokuvamile, izinguquko zokugcina zenzeka ngonyaka wokuqala wokuphila. Kwezinye izingane - esikhathini esivela ezinyangeni ezintathu kuya kwezingu-6, kwabanye - kusukela ezinyangeni ezingu-9 kuya kwezingu-12. I-hue yamehlo ingashintsha ngokungenasici, izuze umbala wokugcina ngeminyaka engu-3 noma engu-4.
Uyazi kanjani umbala wamehlo wengane?
Ukuze unqume umbala wamehlo wengane, ososayensi bezakhi zofuzo baye bahlakulela itafula elikhethekile, elibonisa iphesenti lamathuba ngaphansi kwezimo ezinikeziwe.
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Kodwa-ke, akekho ochwepheshe okwazi ukusho ngokuqiniseka okungu-99% ukuthi yikuphi iris i-baby ezozalwa. Ngaphezu kwalokho, uma kwenzeka ushintsho noma ukuphazanyiswa komsebenzi we-melanocyte, izakhi zofuzo zingenamandla.