11079
Using an oligomer duplex 5 ' - A ( GGGTTA ) ( 5 ) - 3 ' / 5 ' - ( TAACCC ) ( 5 ) T - 3 ' as a template - primer , we show that both the Klenow fragment of Escherichia coli DNA polymerase I and HIV reverse transcriptase could expand telomere DNA sequences as well , giving products greater than the size of the template DNA .
 Klenow fragment of Escherichia coli DNA polymerase I, HIV reverse transcriptase
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 Klenow fragment of Escherichia coli DNA polymerase I, HIV reverse transcriptase