4580
The biological functions of rat surfactant protein A ( SP - A ) , an oligomer composed of 18 polypeptide subunits derived from a single gene , are dependent on intact disulfide bonds .
 GENE: surfactant protein A; GENE: SP - A
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
 GENE: surfactant protein A; GENE: SP - A