USCIS has updated its policy regarding direct sibling-to-sibling DNA testing. If USCIS determined primary evidence is unavailable or unreliable, USCIS may suggest and accept DNA test results from an American Association of Blood Banks (AABB) accredited lab as evidence of a full-or half-sibling relationship. In these cases, USCIS will consider DNA along with all evidence on record to determine if the requisite relationship exists.
A sibling relationship requires that the petitioner and beneficiary are, or once were, the children of at least one common parent. Primary evidence includes birth and marriage certificates. Secondary evidence includes medical records, school records, and religious documents. Affidavits sworn to by persons who were living at the time of and who have personal knowledge of the event to which they attest may also be accepted if certain conditions are met.
USCIS will consider results of DNA testing conducted by an AABB-accredited lab that reflect a 90 percent probability or higher that a full- or half-sibling relationship exists as probative evidence of the claimed relationship. Due to the variations within half-sibling relationship test results, any result for a half sibling below 90 percent will be deemed inconclusive. Where a result is inconclusive, an officer must continue to evaluate the remaining evidence in the totality of the circumstances. To the extent possible, DNA testing against the common parent(s) is encouraged.
美国移民局已更新其关于兄弟姐妹DNA测试的政策。 如果USCIS确定主要证据不可用或不可靠，USCIS可能会建议并接受AABB认可的实验室的DNA测试结果作为兄弟姐妹关系的证据。 在这些情况下，移民局将考虑DNA以及所有记录在案的证据，以确定申请人于受益人是否存在真实的兄弟姐妹关系。
兄弟姐妹关系的请愿者和受益人至少需要有一个共同父母。 主要证据包括出生和结婚证书。 次要证据包括医疗记录，学校记录和宗教文件。 亲戚朋友邻居也可以写信证明他们兄弟姐妹关系的了解程度。