From there, four molecules of Porphobilinogen condense together to form Hydroxymethylbilane with help of Porphobilinogen deaminase.

从这里开始，四分子色素原在色素原的作用下凝聚在起，形成羟色烷。

From there, four molecules of porphobilinogen condense together to form hydroxymethylbilane with the help of porphobilinogen deaminase.

卟原的四个分子并压缩构成，羟素在卟原的辅助下。

Note that porphobilinogen deaminase is sometimes called uroporphyrinogen I synthase or hydroxymethylbilane synthase, or HMBS for short.

卟原有时被称为尿卟啉原I合成或羟素合成，缩略为HMBS。

The diagnosis is confirmed by measuring erythrocyte porphobilinogen deaminase activity.

可通过检测红细胞内卟原活性以确诊。

The majority of individuals with the HMBS gene mutation and a deficiency of porphobilinogen deaminase are asymptomatic.

存在HMBS因突变及缺乏卟原的人群大部分没有症状。

Now individuals with acute intermittent porphyria have a mutation of the HMBS gene which codes for the enzyme porphobilinogen deaminase.

急性间歇性卟啉病的患者存在HMBS因的突变；该因编码卟原。

All right, as a quick recap, acute intermittent porphyria is an autosomal dominant disorder caused by a deficiency of the enzyme porphobilinogen deaminase in the heme synthesis pathway.

好，快速回顾下：急性间歇性卟啉病是常染色体显性疾病，由血红素合成途径中缺乏卟原导致。