This estimated time of origin is decades earlier than the previous estimate of 1930.

此次估计的起源时间比原以为的1930年要早数十年。

They used this and other HIV-1 genetic sequences to construct a family tree of the origin of the viral strain and to estimate the time of origin of HIV-1 group m.

他们利用这个遗传序列与其他HIV - 1的遗传序列构建出起源病毒株的家系图，并以此估算出HIV - 1 M组的起源时间。

If surviving copies are few, the stemma perforce brings into proximity manuscripts that were widely separated in time and place of origin.

如果现存的手稿很少，家谱就必须纳入那些在时间和族地都分散的手稿。