برآورد اندازۀ مؤثر جمعیت در گاو سرابی بر اساس نشانگرهای چندشکل تک‌نوکلئوتیدی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری ژنتیک و اصلاح نژاد دام دانشکدۀ کشاورزی، دانشگاه شهید باهنر کرمان و عضو انجمن پژوهشگران جوان، دانشگاه شهید باهنر کرمان

2 دانشیار گروه علوم دامی، دانشکدۀ کشاورزی، دانشگاه شهید باهنر کرمان

چکیده

این مطالعه با هدف برآورد اندازۀ مؤثر تعداد افراد در حال جفت‌گیری در جمعیت گاو سرابی با روش هتروزیگوسیتی اضافی و بر پایۀ استفاده از نشانگرهای متراکم چندشکل تک‌نوکلئوتیدی انجام گرفت. بدین منظور از 20 رأس گاو سرابی نمونه‌برداری شد. تعیین ژنوتیپ نمونه‌ها با چیپ Illumina High-density Bovine BeadChip شامل 777962 جایگاه SNP صورت گرفت. متوسط هتروزیگوسیتی مورد انتظار، متوسط هتروزیگوسیتی مشاهده‌شده، متوسط فراوانی آلل‌های نادر و درصد آلل‌های در حالت عدم تعادل هاردی-وینبرگ در مجموعۀ داده‌ها برآورد شد. اندازۀ مؤثر تعداد افراد در حال جفت‌گیری بر اساس روش هتروزیگوسیتی اضافی و به کمک نرم‌افزار NEESTIMATOR (v2) به ازای هریک از کروموزوم‌ها جداگانه برآورد شد. متوسط اندازۀ مؤثر برآوردشده، 28 فرد بود و متوسط فاصلۀ اطمینان 95% برای این برآوردها 3/17 تا 2/40 به دست آمد. نتایج مطالعه نشان داد که گاو بومی سرابی در معرض خطر جدی انقراض قرار دارد و تدوین برنامه‌هایی برای حفاظت از گاوهای خالص باقی‌مانده ضروری است.

کلیدواژه‌ها


عنوان مقاله [English]

Estimation of effective population size in Sarabi cattle based on single nucleotide polymorphism markers

نویسندگان [English]

  • Karim Karimi 1
  • Ali Esmaili zadeh koshkueih 2
  • Masoud Asadi Fozi 2
1 Ph. D. Student, Department of Animal Science, Faculty of Agriculture, Shahid Bahonar University of Kerman, and Member of Young Researchers, Shahid Bahonar University of Kerman, Iran
2 Associate Professor, Faculty of Agriculture, Shahid Bahonar University of Kerman, Iran
چکیده [English]

The objective of this study was to estimate the effective number of breeders in Sarabi cattle population using heterozygote-excess method based on single nucleotide polymorphism markers. Data consisted of 20 Sarabi cows. SNP genotyping was performed using Illumina High-density Bovine BeadChip designed to genotype 777,962 SNPs. Average observed heterozygosity, expected heterozygosity, minor allele frequencies and percentage of deviation from Hardy-Weinberg test were estimated. Effective number of breeders was estimated per each chromosome using NEESTIMATOR (v2) software based on heterozygote-excess method. Average chromosome-wise effective number of breeders was equal to 28 and corresponding average confidence interval was between 17.3 and 40.2. Results of this study indicated that Sarabi breed is on serious risk of extinction. Design of appropriate programs is necessary to conserve remaining purebred cattles.

کلیدواژه‌ها [English]

  • effective population size
  • genetic conservation
  • minor allele frequency
  • observed heterozygosity
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