请教一下大家，我家里这个祖源成分，北汉怎么这么高…

{"result":[{"race_desc":"\u4e2d\u534e\u6c11\u65cf","race_en":"chinese_nation","race_probality":"0.999700","area":[{"block":"chinese_nation","race_desc":"\u5317\u65b9\u6c49\u65cf","race_en":"han_northern","race_probality":"0.999590"},{"block":"chinese_nation","race_desc":"\u5176\u4ed6","race_en":"other","race_probality":"0.0002"}]},{"race_desc":"\u5176\u4ed6","race_en":"other","race_probality":"0.0003","area":[]}],"case_id":"ANCESTRY","prefix":null,"description":"\u7956\u6e90\u5206\u6790","color":null,"detail_url":"\/report2\/ancestry\/"} 测了一下一家三口的基因，父亲这边Y系单倍群 N1a1a1a1a4，找到的资料很少看不出什么。
主要想问一下祖源成分，父女俩的祖源成分报告一模一样，但是母亲那边北汉成分只有46%，这种情况真的能做到一点其他基因都不混么……麻烦懂的人帮我分析一下😂