Do you have any knowledge concerning the 101Q mutation? I understand it is an efavirenz mutation.
Dr. Brian Conway responds: It is correct to say that mutations at codon 101 are described as being associated with low-level resistance to all non-nucleoside agents (including efavirenz) in some algorithms. However, in isolation, these mutations are of very little significance. For efavirenz, high-level resistance can be conferred by the combination of the K103N/Y188L mutations or by the accumulation of mutations at codons 100, 106, 181, 190 and 230 (the more of these that are present, the higher the degree of resistance). For the latter pattern, phenotypic testing would be useful to assess the degree of resistance.
The mutation that you describe, especially in isolation, is unlikely to be of any clinical significance. It should be stated that mutations at codon 101 do not appear in the most recent drug resistance mutation table published by the IAS-USA and our group includes only the 101E mutation in our Drug and Mutation Data Pages.
