9503
Recombination and transcription of the endogenous Ig heavy chain locus is effected by the Ig heavy chain intronic enhancer core region in the absence of the matrix attachment regions .
 GENE: endogenous Ig heavy chain locus; GENE: Ig heavy chain intronic enhancer core region
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
 Entities: endogenous Ig heavy chain locus, Ig heavy chain intronic enhancer core region 
Answer:
 GENE: endogenous Ig heavy chain locus; GENE: Ig heavy chain intronic enhancer core region