برآورد میزان هم خونی به روش شجره و نشانگر و تاثیر آن بر صحت پیش بینی ژنومی در داده شبیه سازی

نوع مقاله : مقاله پژوهشی

نویسنده

گروه علوم دامی، دانشکده کشاورزی، دانشگاه ایلام، ایلام، ایران

چکیده

در سالیان گذشته بدلیل عدم شناخت روابط خویشاوندی ژنومی بین افراد جمعیت در گله  تنها از روابط شجره­ای برای کنترل هم ­خونی استفاده می ­شد. در پژوهش کنونی میزان پیشرفت ژنتیکی ( G)، میزان هم ­خونی به روش شجره و میزان هم ­خونی به روش لوکاس IBD برای دو روش GBLUP  و TBLUP برآورد و هم چنین تاثیر آن ­ها بر صحت پیش ­بینی ژنومی به کمک داده شبیه ­سازی بررسی شد. یک جمعیت پایه متشکل از 1000 حیوان برای 4000 نسل به کمک نرم ­افزار QMsim شبیه ­سازی شد. تعداد ده کروموزوم و بر روی هر کروموزوم 1000 نشانگر SNP شبیه ­سازی و تعداد کل QTL ها بر روی ده کروموزوم 1000 عدد در نظر گرفته شد. نتایج پژوهش حاضر نشان داد که  میزان پیشرفت ژنتیکی در روش ارزش اصلاحی ژنومی (GBLUP) 13 درصد بیش تر نسبت به روش TBLUP برآورد شد. میزان هم ­خونی به روش شجره در روش GBLUP بسیار پایین ­تر از روش TBLUP برآورد شد هر چند که در روش هم ­خونی برآورد شده به کمک IBD این میزان تفاوت بسیار ناچیز بود. میزان تفاوت صحت پیش ­بینی ژنومی برای روشی که هم ­خونی به کم نشانگر برآورد شد نسبت به روش شجره، 24 واحد بیش تر به دست آمد. به طور کلی نتایج پژوهش حاضر نشان داد که برآورد میزان هم­ خونی به کم نشانگر از صحت بیش تر برخوردار بوده و تاثیر آن بر صحت پیش­ بینی ژنومی معنی ­دار بود.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Estimation of inbreeding rate by pedigree and marker methods and its effect on the accuracy of genomic prediction in simulation data

نویسنده [English]

  • Yahya Mohammadi
Department of Animal Science, Faculty of Agriculture, Ilam University, Ilam, Iran
چکیده [English]

In the past, pedigree relationships were used to control and monitor inbreeding because genomic relationships among selection candidates were not available until recently. These consequences were measured by genetic gain, pedigree- and genome-based rates of inbreeding, and local inbreeding across the genome. Their effect on the accuracy of genomic predictions was also investigated using simulation data. A baseline population of 1000 animals for 4000 generations was simulated using QMsim software. The number of ten chromosomes and 1000 SNP markers on each chromosome was simulated and the total number of QTLs on ten chromosomes was 1000. The results of the present study showed that the rate of genetic improvement in the genomic breeding value (GBLUP) method was estimated to be 13 percent higher than the TBLUP method. The rate of pedigree inbreeding method in GBLUP method was much lower than TBLUP method, although in the method of inbreeding estimated by IBD this rate was very small. The difference in the accuracy of genomic prediction for the method in which inbreeding was estimated to be low marker was 24 units higher than the pedigree method. In general, the results of the present study showed that the estimate of inbreeding was less accurate and its effect on the accuracy of genomic prediction was significant.

کلیدواژه‌ها [English]

  • Genomic selection accuracy
  • Simulation data
  • Inbreeding rate
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