在人类骨髓移植后，犯罪现场DNA的可靠性受到了质疑

在人类骨髓移植后，犯罪现场DNA的可靠性受到了质疑

When Chris Long received a bone marrow transplant, he knew that the procedure might be the only thing to treat his recent diagnosis of acute myeloid leukemia and myelodysplastic syndromes – two rare conditions that impair the production of healthy blood cells.

当克里斯·朗接受骨髓移植时，他知道这个过程可能是治疗他最近诊断的急性髓系白血病和骨髓增生异常综合征的唯一方法——这两种罕见的情况会损害健康血细胞的产生。

His colleagues saw a scientific opportunity.

他的同事们看到了一个科学机会。

Four years after his treatment, DNA analysis shows that parts of Long now contain more than just stem cells from his donor, a German man who lives thousands of miles away. Lip, cheek, and tongue swabs revealed that his donor’s DNA was present at fluctuating levels throughout the years, while his donor’s DNA had entirely replaced Long’s semen. The only regions that were not affected were his chest and head hair.

在接受治疗四年后，DNA分析显示，朗的部分器官现在不仅含有来自他的捐献者的干细胞，还有来自数千英里之外的德国人。唇、脸颊和舌拭子显示，朗的供体DNA多年来一直处于波动水平，而供体DNA则完全取代了朗的精液。唯一没有受到影响的是他的胸部和头发。

Bone marrow transplants treat blood cancers and blood diseases such as leukemia, lymphoma, and sickle cell anemia. Healthy blood-forming stem cells are inserted into a patient’s bloodstream from a donor to replace unhealthy and poor-producing blood cells – DNA and all, according to the Mayo Clinic.

骨髓移植治疗血癌和血液病，如白血病、淋巴瘤和镰状细胞性贫血。根据梅奥诊所的说法，健康的造血干细胞被从供体移植到患者的血液中，以取代不健康和产生不良血液的细胞——DNA和其他所有细胞。

Long became a chimera of sorts – someone with two sets of DNA. Chimerism in humans is extremely rare with less than 100 documented cases, including a 1953 report published in the British Medical Journal in which a woman was found to contain two types of blood due to cells from her twin brother living in her body. The condition has wreaked havoc on families as well; a man failed his paternity test because a part of his genome belongs to his unborn twin, and a Washington woman was forced to fight for the custody of her child after her genetic makeup did not match that of her children.

朗变成了某种嵌合体——拥有两套DNA的人。人类嵌合症极其罕见，仅有不到100例有文献记载的病例，其中包括1953年发表在《英国医学杂志》(British Medical Journal)上的一份报告，报告中发现一名女性体内存在两种类型的血液，原因是她的孪生兄弟的细胞活在她体内。这种情况也对家庭造成了严重破坏;一名男子未能通过亲子鉴定，因为他的部分基因组属于他未出生的双胞胎，而一名华盛顿妇女由于基因组成与她的孩子不匹配而被迫争夺孩子的监护权。