Молекулярно-генетические основы формирования окраски оперения у кур

Окраска оперения – важный признак у птиц, нередко определяющий принадлежность к тому или иному виду или породе. Окраска является результатом действия веществ, которые поглощают определенную длину волны и формируют так называемые пигментные цвета, и оптическим эффектом, обусловленным интерференцией света, отраженного биологическими микроструктурами пера. Основой для формирования окраски служит синтез меланина. Эумеланин ответственен за черные и коричневые оттенки, а феомеланин отвечает за красновато-коричневые оттенки. Молекулярно-генетический механизм появления того или иного типа окраски еще до конца не изучен, поскольку на один и тот же признак могут влиять несколько генов. Первичная пигментация оперения определяется взаимодействием полиморфных вариантов гена MC1R и генов, участвующих в регуляции меланогенеза. Гены-модификаторы вызывают изменение окраски любого генотипа по локусу E и могут как уменьшать или увеличивать экспрес сию эумеланина, так и разрушать меланоциты. Вторичная пигментация оперения определяется белыми пятнами или специфическим распределением эумеланина на отдельных перьях. Современные методы анализа ДНК, такие как секвенирование, полногеномный анализ с использованием чипов различной плотности, анализ экспрессии генов, позволяют получать новые данные о генах, определяющих окраску оперения.

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