ارزیابی ژن MHC-class IIα درماهی آزاد دریای خزر (Salmo trutta caspius) به روش SSCP

نویسندگان

1 گروه تکثیر و پرورش آبزیان، دانشکده منابع طبیعی و علوم دریایی، دانشگاه تربیت مدرس، صندوق پستی: 46414-356

2 گروه ژنتیک، دانشکده علوم زیستی، دانشگاه تربیت مدرس، صندوق پستی: 175-14115

چکیده

مولکول‌ های MHC در مهره‌ داران نقش‌ مهمی در عملکردسیستم ایمنی اکتسابی داشته و ارزیابی اثرات انتخاب طبیعی و رانش ژنی بر تنوع ژنوم MHC گونه‌ های مختلف بسیار حائز اهمیت می‌ باشد. در این مطالعه تنوع ژنوم MHCگونه بومی و در معرض انقراض ماهی آزاد دریای خزر (Salmo trutta caspius) که مورد حمایت برنامه ‌های بازسازی ذخایر می‌ باشد، مورد بررسی قرار گرفت. ازاین ‌رو تنوع جایگاه DAA ژن MHC کلاس αII در 50 نمونه ماهی آزاد دریای خزر با استفاده از روش SSCP بررسی شد. نتایج تحقیق نشان می ‌دهد که این ژن حداقل واجد 15 الل می‌ باشد که الل‌ های MHCScCa-DAA*03 و MHCScCa-DAA*10 دارای بیش ‌ترین فراوانی می ‌باشند. هم‌ چنین هتروزایگوسیتی مشاهده شده (HO)، مورد انتظار (He) و شاخص شانون به ‌ترتیب برابر 0/82،0/80 و 2/037 می‌ باشد. در جمع ‌بندی باید بیان کرد، علی‌رغم تنوع بالای ژنوم MHC در ماهی آزاد دریای خزر، ولی با توجه به وضعیت حفاظتی در حال انقراض و دستکاری‌ های انسانی، بسیاری از الل‌ هایی که فراوانی پایین دارند در خطر از دست رفتن می‌ باشند. ازاین ‌رو توجه به حفظ تنوع این ژنوم طی برنامه‌ های بازسازی ذخایر ماهی آزاد دریای خزر حائز اهمیت می‌ باشد.

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