# POSITION AA CATEGORY SCORE COMMENT 10 IVFRY PIMinor Yes L10I/V/F/R/Y are associated with resistance to most PIs when present with other mutations. L10I/V occur in 5-10% of untreated persons. L10F/R/Y are nonpolymorphic. 10 NOT IVFRY Other L10I/V/F/R/Y are associated with resistance to most PIs when present with other mutations. $listMutsIn{10(NOT IVFRY)} is a highly unusual mutation at this position. 11 I PIMinor Yes V11I is a PI-selected mutation. It is one of the 11 mutations associated with decreased response to DRV/r in the POWER trials. 11 NOT I Other None 13 V Other No I13V is a common polymorphism that is more common in treated than untreated subtype B isolates. In several subtypes, it is the consensus residue. 13 NOT V Other None 16 E Other No G16E is highly polymorphic. G16E was weakly associated with ATV/r therapy in one study. 16 NOT E Other None 20 RMITV Other No K20R/M/I/T/V are associated with resistance to multiple PIs when present with other mutations. K20R/M/I are polymorphic; K20T/V are nonpolymorphic. 20 NOT RIMTV Other K20R/M/I/T/V are associated with resistance to multiple PIs when present with other mutations. $listMutsIn{20(NOT RIMTV)} is a highly unusual mutation at this position. 23 I PIMajor Yes L23I is a rare substrate cleft mutation that causes low-level NFV resistance. 23 NOT I PIMinor L23I is a rare substrate cleft mutation that causes low-level NFV resistance. $listMutsIn{23(NOT I)} is a highly unusual mutation at this position. 24 F PIMinor Yes L24I is associated with reduced susceptibility to IDV/r and possibly LPV/r, SQV/r, and ATV/r when present with other mutations. It increases TPV/r susceptibility. L24F is a rare mutation at this position; its phenotypic effect is not known. 24 I PIMajor Yes L24I is associated with reduced susceptibility to IDV/r and possibly LPV/r, SQV/r, and ATV/r when present with other mutations. It increases TPV/r susceptibility. 24 NOT FI Other L24I is associated with reduced susceptibility to IDV/r and possibly LPV/r, SQV/r, and ATV/r when present with other mutations. It increases TPV/r susceptibility. L24F is a rare mutation at this position; its phenotypic effect is not known. $listMutsIn{24(NOT FI)} is a highly unusual mutation at this position. 30 N PIMajor Yes D30N causes high-level resistance to NFV and potential low-level resistance to ATV/r. 30 NOT N PIMajor D30N causes high-level resistance to NFV and potential low-level resistance to ATV/r. $listMutsIn{D30(NOT N)} is a highly unusual mutation at this position. 32 I PIMajor Yes V32I is a substrate cleft mutation which is associated with reduced susceptibility to all PIs except SQV/r. 32 NOT I PIMajor V32I is a substrate cleft mutation which is associated with reduced susceptibility to all PIs except SQV/r. $listMutsIn{V32(NOT I)} is a highly unusual mutation at this position. 33 F PIMajor Yes L33F are selected by FPV/r, DRV/r, LPV/r, ATV/r, and TPV/r, and contribute resistance to these drugs. 33 I PIMinor Yes L33F are selected by FPV/r, DRV/r, LPV/r, ATV/r, and TPV/r, and contribute resistance to these drugs. L33I is less common than L33F but may have a similar effect. 33 V Other Yes L33V is a polymorphism that does not appear to be related to PI therapy or drug resistance. 33 NOT FIV Other None 35 G PIMinor Yes E35G is a nonpolymorphic mutation that is selected by NFV and which is weakly associated with decreased virological response to TPV/r. 35 NOT G Other None 36 I Other No M36I is weakly associated with PI resistance in subtype B viruses when present with other mutations. However, M36I is the consensus amino acid in most non-B subtypes. 36 LTV Other No M36I is weakly associated with PI resistance in subtype B viruses when present with other mutations. However, M36I is the consensus amino acid in most non-B subtypes. M36L/V/T are uncommon mutations at this position of unknown significance. 36 NOT ILTV Other None 43 T PIMinor Yes K43T is a nonpolymorphic PI-selected mutation. It was associated with a decreased virological response to TPV/r in the RESIST trials. 43 NOT T Other None 46 IL PIMajor Yes M46I/L decreases susceptibility to IDV/r, NFV, FPV/r, LPV/r, and ATV/r when present with other mutations. 46 V PIMinor Yes M46I/L decreases susceptibility to IDV/r, NFV, FPV/r, LPV/r, and ATV/r when present with other mutations. M46V is an uncommon PI-selected mutation at this position. 46 NOT ILV PIMinor M46I/L decreases susceptibility to IDV/r, NFV, FPV/r, LPV/r, and ATV/r when present with other mutations. M46V is an uncommon PI-selected mutation at this position. $listMutsIn{46(NOT ILV)} is a highly unusual mutation at this position. 47 A PIMajor Yes I47A usually occurs with V32I and in this setting causes high-level LPV/r and FPV/r resistance and possibly decreased DRV/r susceptibility. 47 V PIMajor Yes I47V decrease susceptibility to FPV/r, ATV/r, IDV/r, LPV/r, TPV/r, and DRV/r. 47 NOT AV PIMajor I47V decrease susceptibility to FPV/r, ATV/r, IDV/r, LPV/r, TPV/r, and DRV/r. I47A usually occurs with V32I and in this setting causes high-level LPV/r and FPV/r resistance and possibly decreased DRV/r susceptibility. $listMutsIn{47(NOT AV)} is a highly unusual mutation at this position. 48 ASTQ PIMinor Yes G48V causes high-level SQV/r resistance, intermediate ATV/r and NFV resistance, and low-level IDV/r and LPV/r resistance. G48M has not been well studied but may have a similar effect on ARV susceptibility. G48A/S/T/Q are rare PI-selected mutations. 48 M PIMajor Yes G48V causes high-level SQV/r resistance, intermediate ATV/r and NFV resistance, and low-level IDV/r and LPV/r resistance. G48M is a less common mutation that may have a similar effect on ARV susceptibility. 48 V PIMajor Yes G48V causes high-level SQV/r resistance, intermediate ATV/r and NFV resistance, and low-level IDV/r and LPV/r resistance. 48 NOT VMASTQ PIMinor G48V causes high-level SQV/r resistance, intermediate ATV/r and NFV resistance, and low-level IDV/r and LPV/r resistance. G48M/A/S/T/Q are uncommon PI-selected mutations of uncertain effects. $listMutsIn{48(NOT VMASTQ)} is a highly unusual mutation at this position. 50 L PIMajor Yes I50L causes intermediate-to-high level resistance to ATV/r and increased susceptibility to the remaining PIs. 50 V PIMajor Yes I50V causes intermediate-to-high-level resistance to FPV/r, low-intermediate resistance to LPV/r and DRV/r, and increased susceptibility to TPV/r. 50 NOT LV PIMajor I50V causes intermediate-to-high-level resistance to FPV/r, low-intermediate resistance to LPV/r and DRV/r, and increased susceptibility to TPV/r. I50L causes intermediate-to-high level resistance to ATV/r and increased susceptibility to the remaining PIs. $listMutsIn{50(NOT LV)} is a highly unusual mutation at this position. 53 L PIMajor Yes F53L is associated with decreased susceptibility to SQV/r and possibly ATV/r, IDV/r, NFV, and LPV/r. 53 Y PIMinor Yes F53L is associated with decreased susceptibility to SQV/r and possibly ATV/r, IDV/r, NFV, and LPV/r. F53Y is a rare treatment-associated variant at this position. 53 NOT LY PIMinor F53L is associated with decreased susceptibility to SQV/r and possibly ATV/r, IDV/r, NFV, and LPV/r. $listMutsIn{53(NOT LY)} is a highly unusual mutation at this position. 54 TAS PIMajor Yes I54T/A/S are PI-related mutations that appear to be associated with decreased susceptibility to each of the PIs. But their effects have not been as well studied as I54V, I54M, or I54L. 54 L PIMajor Yes I54L occurs in patients receiving FPV/r, LPV/r, and DRV/r and reduces susceptibility to these drugs and to NFV and possibly ATV/r. It increases TPV/r susceptibility. 54 M PIMajor Yes I54M occurs in patients receiving FPV/r, LPV/r, and DRV/r and reduces susceptibility to these drugs and to the remaining PIs except possibly SQV/r. 54 V PIMajor Yes I54V contributes resistance to each of the PIs except TPV/r and DRV/r. 54 NOT ALMSTV PIMajor I54V/M/L/A/T/S have diverse effects on multiple PIs. $listMutsIn{54(NOT ALMSTV)} is a highly unusual mutation at this position. 58 E PIMinor Yes Q58E is a nonpolymorphic PI-selected mutation associated with decreased susceptibility to TPV/r and possibly other PIs. 58 NOT E Other None 60 E Other No D60E is a polymorphic mutation that is slightly more common in viruses from PI-treated compared with untreated persons. 60 NOT E Other None 62 V Other No I62V is a highly polymorphic mutation that is more common in PI-treated compared with untreated persons. 62 NOT V Other None 63 P Other No L63P is a common polymorphism that becomes even more common in persons receiving PIs. 63 NOT P Other None 71 TVIL PIMinor Yes A71T/V are polymorphisms that occur in 2-3% of untreated persons but which increase in frequency in persons receiving PIs. A71I/L are nonpolymorphic mutations that occur in viruses with multiple PI-resistance mutations. 71 NOT TVIL Other None 73 STCA PIMinor Yes G73S/T/C/A are selected by and appear to be associated with decreased susceptibility to most, if not all, PIs. Their effect on SQV/r and NFV and possibly ATV/r appears to be greater than their effect on other PIs. 73 NOT STCA Other None 74 P PIMinor Yes T74P is a nonpolymorphic mutation that occurs more commonly in heavily treated patients. It has been associated with decreased virological response to TPV/r and to a lesser extent DRV/r but is probably associated with decreased susceptibility to multiple PIs. 74 S PIMinor Yes T74S is associated with reduced NFV susceptibility. It occurs in untreated persons with subtype C viruses. 74 NOT PS Other None 76 V PIMajor Yes L76V reduces susceptibility to FPV/r, IDV/r, LPV/r, and DRV/r and increases susceptibility to SQV/r, ATV/r, and TPV/r. 76 NOT V PIMinor L76V reduces susceptibility to FPV/r, IDV/r, LPV/r, and DRV/r and increases susceptibility to SQV/r, ATV/r, and TPV/r. $listMutsIn{76(NOT V)} is a highly unusual mutation at this position. 77 I Other No V77I is a common polymorphism that is associated with NFV therapy. 77 NOT I None 82 A PIMajor Yes V82A reduces susceptibility to IDV/r and LPV/r. With other mutations it is associated with reduced susceptibility to NFV, ATV/r, SQV/r, and FPV/r. 82 C PIMajor Yes V82C is a rare mutation that occurs primarily in protease genes containing multiple other PI-resistance mutations. 82 F PIMajor Yes V82F reduces susceptibility to IDV/r, LPV/r, FPV/r, and possibly DRV/r. With other mutations it is associated with reduced susceptibility to NFV, ATV/r, SQV/r, and possibly TPV/r. 82 I Other Yes V82I is a polymorphism that is common in some non-B subtypes; it has little if any effect on PI susceptibility. 82 L PIMajor Yes V82L is a rare TPV/r-selected mutation which decreases TPV/r susceptibility. Its effect on other PIs has not been characterized. 82 M PIMajor Yes V82M reduces IDV/r susceptibility in subtype G viruses. Its effect on other PIs has not been studied. 82 S PIMajor Yes V82S probably has a similar effect to V82T which reduces susceptibility to IDV/r, LPV/r, and TPV/r and with other mutations is associated with reduced susceptibility to NFV, ATV/r, FPV/r, and SQV/r. 82 T PIMajor Yes V82T reduces susceptibility to IDV/r, LPV/r, and TPV/r. With other mutations it is associated with reduced susceptibility to NFV, ATV/r, FPV/r, and SQV/r. 82 NOT ATIFLMSC PIMajor V82A/T/F/L/M/S/C have diverse effects on multiple PIs. $listMutsIn{82(NOT ACFILMST)} is a highly unusual mutation at this position. 83 D PIMinor Yes N83D is a nonpolymorphic mutation that occurs more commonly in heavily treated patients. It has been associated with decreased virological response to TPV/r. Its effect on other PIs is not known. 83 NOT D PIMinor N83D is a nonpolymorphic mutation that occurs more commonly in heavily treated patients. It has been associated with decreased virological response to TPV/r. Its effect on other PIs is not known. $listMutsIn{83(NOT D)} is a highly unusual mutation at this position. 84 AC PIMajor Yes I84V causes intermediate/high-level resistance to ATV/r, FPV/r, IDV/r, NFV, and SQV/r; and low-level resistance to LPV/r, TPV/r, and DRV/r. I84A/C are rare mutations that like I84V appear to reduce susceptibility to each of the PIs. 84 V PIMajor Yes I84V causes intermediate/high-level resistance to ATV/r, FPV/r, IDV/r, NFV, and SQV/r; and low-level resistance to LPV/r, TPV/r, and DRV/r. 84 NOT ACV PIMajor I84V causes intermediate/high-level resistance to ATV/r, FPV/r, IDV/r, NFV, and SQV/r; and low-level resistance to LPV/r, TPV/r, and DRV/r. I84A/C are rare mutations that like I84V appear to reduce susceptibility to each of the PIs. $listMutsIn{84(NOT ACV)} is a highly unusual mutation at this position. 85 V PIMinor Yes I85V is a nonpolymorphic PI-selected mutation. 85 NOT V Other None 88 D PIMajor Yes N88D is selected by NFV and, in combination with D30N, increases NFV resistance. 88 GT PIMinor Yes N88S causes high-level resistance to NFV and ATV/r and low-level resistance to IDV/r; it increases susceptibility to FPV/r. N88T/G are rare PI-selected mutations that may have an effect similar to but less pronounced than N88S. 88 S PIMajor Yes N88S causes high-level resistance to NFV and ATV/r and low-level resistance to IDV/r; it increases susceptibility to FPV/r. 88 NOT DGST PIMinor N88D/S/T/G have diverse effects on several PIs. $listMutsIn{88(NOT DGST)} is a highly unusual mutation at this position. 89 V PIMinor Yes L89V is a nonpolymorphic PI-selected accessory mutation which emerges during treatment with DRV/r and NFV. It is also one of the 11 mutations associated with decreased response to DRV/r in the POWER trials. 89 I Other No L89I is a minimally polymorphic PI-selected mutation of uncertain effect on PI susceptibility. 89 T Other No L89T is a nonpolymoprhic PI-selected mutation of uncertain effect on PI susceptibility. 89 M Other No L89M is a common polymorphism that is not associated with decreased PI susceptibility. 89 NOT VITM Other None 90 M PIMajor Yes L90M causes resistance to NFV, SQV/r, ATV/r, and IDV/r. When present with other mutations it also decreases the activity of FPV/r and LPV/r. 90 NOT M PIMajor L90M causes resistance to NFV, SQV/r, ATV/r, and IDV/r. When present with other mutations it also decreases the activity of FPV/r and LPV/r. $listMutsIn{90(NOT M)} is a highly unusual mutation at this position. 93 M Other No I93M is a rare PI-associated mutation; its effect on PI susceptibility is not known. 93 L Other No I93L is a common polymorphism. It is the consensus residue in most subtypes. In subtype B, it is weakly associated with PI treatment. 93 NOT LM Other None