840
The seven exons , the exon / intron boundaries and part of 3 noncoding sequence of the CPO gene were systematically analyzed by an exon - by - exon denaturing gradient gel electrophoresis ( DGGE ) strategy followed by direct sequencing in seven unrelated heterozygous HC patients from France , Holland , and Czech Republic .
 Disease: HC
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease 
Text: {0} 
Answer:
 Disease: HC