1. 冰岛的一个研究剖明，要是是第三或第四代的表亲结为良俦，他们孙辈的存活率比明日亲成婚可能是基因相差很远的良俦的都要高。
" A study in Iceland showed that partners who are third or fourth cousins have more surviving grandchildren than people who are either more closely related or less closely related, " she said.
2. 冰岛的一个研究剖明，要是是第三或第四代的表亲结为良俦，他们孙辈的存活率比明日亲成婚可能是基因相差很远的良俦的都要高。
" A study in Iceland showed that partners who are third or fourth cousins have more surviving grandchildren than people who are either more closely related or less closely related," she said.