Sequencecomparison revealed that NS4A was one of the most conservative genes. NS4A gene of Shimenstrain has a very high homology with ALD, GPE -, HCLV, and Brescia strain. And the deduced amino acid sequences homologies are as high as 100% .

• 序列比较表明，该基因为最保守的基因之一，其中石门株序列与ALD，GPE，HCLV及Brescia株均有很高的同源性，由其推导的氨基酸的同源性高达100%25。