<?xml version="1.0" encoding="utf-8"?> <text> <s id="1"> <w id="w1.1">O</w> <w id="w1.2">albinismo</w> <w id="w1.3">,</w> <w id="w1.4">vem</w> <w id="w1.5">do</w> <w id="w1.6">latim</w> <w id="w1.7">albus</w> <w id="w1.8">,</w> <w id="w1.9">significa</w> <w id="w1.10">branco</w> <w id="w1.11">,</w> <w id="w1.12">é</w> <w id="w1.13">um</w> <w id="w1.14">grupo</w> <w id="w1.15">de</w> <w id="w1.16">desordens</w> <w id="w1.17">hereditárias</w> <w id="w1.18">em</w> <w id="w1.19">que</w> <w id="w1.20">a</w> <w id="w1.21">biossíntese</w> <w id="w1.22">do</w> <w id="w1.23">pigmento</w> <w id="w1.24">de</w> <w id="w1.25">melanina</w> <w id="w1.26">está</w> <w id="w1.27">ausente</w> <w id="w1.28">ou</w> <w id="w1.29">reduzida</w> <w id="w1.30">.</w> </s> <s id="2"> <w id="w2.1">Atualmente</w> <w id="w2.2">é</w> <w id="w2.3">classificado</w> <w id="w2.4">de</w> <w id="w2.5">acordo</w> <w id="w2.6">com</w> <w id="w2.7">o</w> <w id="w2.8">gene</w> <w id="w2.9">afetado</w> <w id="w2.10">e</w> <w id="w2.11">não</w> <w id="w2.12">mais</w> <w id="w2.13">como</w> <w id="w2.14">parcial</w> <w id="w2.15">ou</w> <w id="w2.16">total</w> <w id="w2.17">,</w> <w id="w2.18">tirosinase</w> <w id="w2.19">positivo</w> <w id="w2.20">ou</w> <w id="w2.21">tirosinase</w> <w id="w2.22">negativo</w> <w id="w2.23">.</w> </s> <s id="3"> <w id="w3.1">O</w> <w id="w3.2">gene</w> <w id="w3.3">para</w> <w id="w3.4">a</w> <w id="w3.5">tirosinase</w> <w id="w3.6">no</w> <w id="w3.7">cromossomo</w> <w id="w3.8">11q14-21</w> <w id="w3.9">e</w> <w id="w3.10">o</w> <w id="w3.11">gene</w> <w id="w3.12">P</w> <w id="w3.13">no</w> <w id="w3.14">cromossomo</w> <w id="w3.15">15q11.2</w> <w id="w3.16">são</w> <w id="w3.17">os</w> <w id="w3.18">genes</w> <w id="w3.19">mais</w> <w id="w3.20">comumente</w> <w id="w3.21">afetadas</w> <w id="w3.22">,</w> <w id="w3.23">as</w> <w id="w3.24">mutações</w> <w id="w3.25">nestes</w> <w id="w3.26">genes</w> <w id="w3.27">causam</w> <w id="w3.28">albinismo</w> <w id="w3.29">oculocutâneo</w> <w id="w3.30">tipo1</w> <w id="w3.31">OCA1</w> <w id="w3.32">;</w> <w id="w3.33">OMIM203100</w> <w id="w3.34">e</w> <w id="w3.35">oculocutâneo</w> <w id="w3.36">tipo</w> <w id="w3.37">2</w> <w id="w3.38">OCA2</w>