19701
However , the average frequency of the minor mtDNA haplotype is low ( 0 . 8 % ) , which suggests that this pervasive heteroplasmy has not been noticed before due to a lack of power in sequencing surveys .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None