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ALBINIZM

albinizmALBINIZM (lot. albus – safed), vuchud nadoshtani pigmentatsiyai muqarrari dar odam (rangi muqarrarii muy, pust, pardai chashm va g.). A. alomati irsi buda, az mavchudiyati geni retsessivi, ki dar holati gomozigoti sintezi pigmentho (melanin) – ro bozmedorad, vobastagi dorad. Dar odam koeffisienti zuhuroti A., yane mavchud budani geni A. dar holati gomozigoti, barobari 1:20000 ast. Bino ba aqidai olimon sababi A. nabudani fermenti tirozinaza, ki bahri sintezi melanin ahamiyati kalon dorad, mahsub meshavad. Dar genhoe, ki hosil shudani tirozinazaro ba uhda dorand, metavonand noqisihoi gunogun rukh namoyand.
Melanin dar melanosomai melanositho tashakkul meyobad. Melanositho dar pust, muy va boftahoi rangbakhshi chashm vujud dorand. Dar mavridi A. rangi muy, pust, chashm tagyir meyobad; goho faqat rangi chashm digargun meshavadu bas.
A. imkon dorad, ki boisi illathoi gunogun – nazdikbini, astigmatizm, hassosiyati baland ba tasiri rushnoi va g. gardad. Pust va mui ashkhosi giriftori A. safed buda, chashmashon surkh metobad. A. dar bayni hamai khalqiyatho duchor meoyad. On khususan dar bayni siyohpustoni Amerikai SHimoli, hindiyoni shtati Arizona, Meksika, sokinoni Sitsiliya beshtar ba mushohida merasad. A. juzi niz meshavad. Dar mavridi on dar pust doghoi safed ba vujud meoyand, vale rangi aslii pust va chashmon boqi memonad (goho rangi muy niz safed ast). A. muolija nameshavad. CHunin odamon boyad khudro az tasiri oftob hifz kunand, ba chashm aynaki siyoh girand. H. J. Usmonova.

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