50 - 基因组预测的基础(4) - ssGBLUP和H矩阵
2022-07-21 本文已影响0人
Hello育种
ssGBLUP经过10多年的发展,已经普遍开始应用在动物育种中。
以前的多步法
![](https://img.haomeiwen.com/i24959989/46118cebdb1f046c.png)
基因组评估
![](https://img.haomeiwen.com/i24959989/6591f3b0d5c74b61.png)
问题:
![](https://img.haomeiwen.com/i24959989/4289b0c925a80646.png)
表型的测量
![](https://img.haomeiwen.com/i24959989/78610aa80b6573f7.png)
![](https://img.haomeiwen.com/i24959989/37bd421041d85116.png)
BLUP会低估基因组选择趋势
![](https://img.haomeiwen.com/i24959989/27761ebf9da9e9bd.png)
一步法(ssGBLUP)
![](https://img.haomeiwen.com/i24959989/6ccf0b008a653419.png)
展开的内容
![](https://img.haomeiwen.com/i24959989/4d39fba944fb474a.png)
![](https://img.haomeiwen.com/i24959989/e66edb1dc38d671a.png)
基因型的点估计问题
![](https://img.haomeiwen.com/i24959989/9d826151c14691c2.png)
假设基因型被视为特征
![](https://img.haomeiwen.com/i24959989/4523f33118b95994.png)
使用 BLUP预测个体的基因组(Gengler's method)
![](https://img.haomeiwen.com/i24959989/b321bdcf51c5a0c6.png)
例如:
![](https://img.haomeiwen.com/i24959989/11be245908fef3ee.png)
增强基因型
Gengler 等人。 (2007) 构思了一种代数方法来处理这些点估计。
![](https://img.haomeiwen.com/i24959989/b8aeb3ddf43ee8d0.png)
缺失数据在经典处理
![](https://img.haomeiwen.com/i24959989/0347ce7fe092ac0d.png)
fancy- 填充
![](https://img.haomeiwen.com/i24959989/2ba7e92791402a21.png)
一步法是 将没有基因型动物作为缺失值处理
![](https://img.haomeiwen.com/i24959989/1be22054b7e1a12b.png)
推断基因型
![](https://img.haomeiwen.com/i24959989/89025b804b1533d7.png)
另一种不推断基因型,因为我们需要的是个体育种值
![](https://img.haomeiwen.com/i24959989/fc37422aaf8d9540.png)
![](https://img.haomeiwen.com/i24959989/cde7f54a32718afb.png)
所有动物的协方差
![](https://img.haomeiwen.com/i24959989/58843467b1b485e3.png)
![](https://img.haomeiwen.com/i24959989/c4388165523c73d3.png)
![](https://img.haomeiwen.com/i24959989/88cdf361d1d70484.png)
两个创建ssGBLUP的想法
![](https://img.haomeiwen.com/i24959989/1c2c7c15b4274efb.png)
第一种:
![](https://img.haomeiwen.com/i24959989/b66bdc0c3d81fdd6.png)
联合分布
![](https://img.haomeiwen.com/i24959989/934ed16ebcba8a80.png)
![](https://img.haomeiwen.com/i24959989/bf363b99ccf2be66.png)
![](https://img.haomeiwen.com/i24959989/3ac4be608c88d1cb.png)
![](https://img.haomeiwen.com/i24959989/8c3ee157cddb8940.png)
![](https://img.haomeiwen.com/i24959989/dbf685d4c0b60e57.png)
转为所有个体的协方差
![](https://img.haomeiwen.com/i24959989/7d5e38b721929a50.png)
H的逆很容易求出:
![](https://img.haomeiwen.com/i24959989/f093106fd3df7500.png)
理解H矩阵
![](https://img.haomeiwen.com/i24959989/9eaf860ebcd525e6.png)
![](https://img.haomeiwen.com/i24959989/27417fc8f187373a.png)
H矩阵的例子
![](https://img.haomeiwen.com/i24959989/733e223912b28f60.png)
![](https://img.haomeiwen.com/i24959989/f1db5150fc08203a.png)
![](https://img.haomeiwen.com/i24959989/9f80b070ef0027b9.png)
![](https://img.haomeiwen.com/i24959989/e6e16826c1eb7e4f.png)
更复杂的例子
![](https://img.haomeiwen.com/i24959989/9b84436f61047a50.png)
![](https://img.haomeiwen.com/i24959989/05e604f3a552a829.png)
![](https://img.haomeiwen.com/i24959989/bb6fdd7ce9ac6a24.png)
![](https://img.haomeiwen.com/i24959989/71b8ba654389055a.png)
![](https://img.haomeiwen.com/i24959989/1493a2012983d8db.png)
H矩阵的一些特点
![](https://img.haomeiwen.com/i24959989/14c08d09e1fc279b.png)
![](https://img.haomeiwen.com/i24959989/e6041a57c9f9ddcf.png)
ssGBLUP的混合方程组
![](https://img.haomeiwen.com/i24959989/b9ca27f3f892131f.png)
![](https://img.haomeiwen.com/i24959989/5299fe5c3de0a535.png)
![](https://img.haomeiwen.com/i24959989/742a467f26d5d09c.png)
目前ssGBLUP的拓展模型
![](https://img.haomeiwen.com/i24959989/4a74eb89e667f874.png)