Incidental Mutation 'R4706:Zfp39'
ID 355242
Institutional Source Beutler Lab
Gene Symbol Zfp39
Ensembl Gene ENSMUSG00000037001
Gene Name zinc finger protein 39
Synonyms Zfp-39, CTfin33
MMRRC Submission 041954-MU
Accession Numbers
Essential gene? Probably non essential (E-score: 0.153) question?
Stock # R4706 (G1)
Quality Score 225
Status Not validated
Chromosome 11
Chromosomal Location 58778979-58795051 bp(-) (GRCm39)
Type of Mutation missense
DNA Base Change (assembly) A to G at 58793633 bp (GRCm39)
Zygosity Heterozygous
Amino Acid Change Valine to Alanine at position 35 (V35A)
Ref Sequence ENSEMBL: ENSMUSP00000099764 (fasta)
Gene Model predicted gene model for transcript(s): [ENSMUST00000102703]
AlphaFold Q02525
Predicted Effect probably benign
Transcript: ENSMUST00000102703
AA Change: V35A

PolyPhen 2 Score 0.408 (Sensitivity: 0.89; Specificity: 0.90)
SMART Domains Protein: ENSMUSP00000099764
Gene: ENSMUSG00000037001
AA Change: V35A

DomainStartEndE-ValueType
KRAB 59 119 8.23e-34 SMART
low complexity region 171 180 N/A INTRINSIC
ZnF_C2H2 298 320 9.58e-3 SMART
ZnF_C2H2 326 347 2.2e2 SMART
ZnF_C2H2 353 373 1.18e2 SMART
ZnF_C2H2 409 431 8.34e-3 SMART
ZnF_C2H2 437 459 7.26e-3 SMART
ZnF_C2H2 465 487 1.53e-1 SMART
ZnF_C2H2 493 515 9.08e-4 SMART
ZnF_C2H2 521 543 2.61e-4 SMART
ZnF_C2H2 549 571 1.12e-3 SMART
ZnF_C2H2 577 599 4.94e-5 SMART
ZnF_C2H2 605 627 5.14e-3 SMART
ZnF_C2H2 633 655 1.38e-3 SMART
ZnF_C2H2 661 683 6.78e-3 SMART
ZnF_C2H2 689 711 5.14e-3 SMART
Predicted Effect noncoding transcript
Transcript: ENSMUST00000148244
Coding Region Coverage
  • 1x: 99.2%
  • 3x: 98.5%
  • 10x: 97.1%
  • 20x: 94.8%
Validation Efficiency
MGI Phenotype FUNCTION: [Summary is not available for the mouse gene. This summary is for the human ortholog.] This gene encodes a Kruppel-associated box (KRAB) zinc-finger protein, which belongs to a large group of transcriptional regulators in mammals. These proteins bind nucleic acids and play important roles in various cellular functions, including cell proliferation, differentiation and apoptosis, and in regulating viral replication and transcription. A pseudogene of this gene was identified on chromosome 1. [provided by RefSeq, May 2016]
Allele List at MGI
Other mutations in this stock
Total: 78 list
GeneRefVarChr/LocMutationPredicted EffectZygosity
Abca16 T A 7: 120,064,988 (GRCm39) N548K probably damaging Het
Abcd2 T C 15: 91,043,385 (GRCm39) D601G probably benign Het
Afap1l2 A T 19: 56,925,672 (GRCm39) I152N possibly damaging Het
Ankrd52 T G 10: 128,214,030 (GRCm39) M62R probably benign Het
Aox4 A T 1: 58,305,946 (GRCm39) T1317S probably damaging Het
Apol7c T A 15: 77,409,923 (GRCm39) Q341L probably benign Het
Arhgef4 C T 1: 34,771,298 (GRCm39) R1202W probably benign Het
B4galnt2 C T 11: 95,766,923 (GRCm39) probably null Het
Cecr2 A T 6: 120,732,539 (GRCm39) E477V possibly damaging Het
Chmp7 A T 14: 69,956,010 (GRCm39) D419E probably benign Het
Cmip A C 8: 118,103,893 (GRCm39) K127T probably damaging Het
Csmd2 T C 4: 128,438,544 (GRCm39) V3041A probably benign Het
Cyp1b1 T A 17: 80,020,771 (GRCm39) I324F possibly damaging Het
Dapp1 T C 3: 137,638,928 (GRCm39) D225G probably benign Het
Ddx10 T C 9: 53,145,231 (GRCm39) T249A probably damaging Het
Dscaml1 T C 9: 45,361,878 (GRCm39) Y213H probably damaging Het
Eef1a2 T C 2: 180,797,150 (GRCm39) D17G probably damaging Het
Fbn1 T C 2: 125,212,069 (GRCm39) I848V probably benign Het
Fbxw18 A G 9: 109,519,585 (GRCm39) I307T probably benign Het
Fxr1 T A 3: 34,118,278 (GRCm39) D500E probably damaging Het
Gars1 G A 6: 55,046,363 (GRCm39) G492D probably damaging Het
Gria2 A T 3: 80,648,297 (GRCm39) D146E probably benign Het
Gstz1 A G 12: 87,205,894 (GRCm39) N37S probably benign Het
Hnrnph3 C A 10: 62,853,059 (GRCm39) G194V probably damaging Het
Il2rb T C 15: 78,370,600 (GRCm39) R172G possibly damaging Het
Itga11 T A 9: 62,662,578 (GRCm39) V517D possibly damaging Het
Kcnq4 A G 4: 120,561,683 (GRCm39) I462T probably benign Het
Klf6 T A 13: 5,911,639 (GRCm39) M1K probably null Het
Lrp8 G A 4: 107,718,470 (GRCm39) A817T probably benign Het
Map3k5 T A 10: 19,934,684 (GRCm39) Y509N probably damaging Het
Mdc1 C T 17: 36,163,671 (GRCm39) S1073F probably damaging Het
Mme A G 3: 63,256,133 (GRCm39) D531G possibly damaging Het
Mrc2 G A 11: 105,239,257 (GRCm39) probably null Het
Mroh7 A T 4: 106,548,821 (GRCm39) V1014E possibly damaging Het
Msantd5l A T 11: 51,144,668 (GRCm39) F204L possibly damaging Het
Myo1d C T 11: 80,557,467 (GRCm39) C491Y probably damaging Het
Ncoa3 C A 2: 165,889,799 (GRCm39) D61E probably damaging Het
Nmrk1 A G 19: 18,622,491 (GRCm39) E190G probably benign Het
Nr4a2 G T 2: 57,002,225 (GRCm39) P13H probably damaging Het
Nup205 T C 6: 35,178,943 (GRCm39) L671P probably damaging Het
Omt2a T C 9: 78,220,352 (GRCm39) I16V probably benign Het
Or4c116 A T 2: 88,942,576 (GRCm39) F93L probably damaging Het
Or51f2 T A 7: 102,526,640 (GRCm39) H104Q probably damaging Het
Or6n1 A G 1: 173,917,268 (GRCm39) I221V probably damaging Het
Or8k24 G A 2: 86,216,732 (GRCm39) T10I probably benign Het
Or8s5 G T 15: 98,238,659 (GRCm39) H70Q possibly damaging Het
Osbpl9 A T 4: 109,013,884 (GRCm39) I70N probably damaging Het
Pclo A T 5: 14,764,221 (GRCm39) L4231F unknown Het
Per1 C T 11: 68,991,444 (GRCm39) probably benign Het
Perm1 G T 4: 156,301,531 (GRCm39) C25F probably damaging Het
Phf3 A G 1: 30,844,687 (GRCm39) V1424A probably damaging Het
Plxnb1 T G 9: 108,941,096 (GRCm39) L1625R probably damaging Het
Ppid G A 3: 79,506,359 (GRCm39) V216I probably benign Het
Ppp4r3a C T 12: 101,008,175 (GRCm39) G754D probably damaging Het
Prex2 G T 1: 11,270,212 (GRCm39) W1299L probably damaging Het
Ptprn2 C A 12: 116,835,714 (GRCm39) Q350K probably benign Het
Ralyl G A 3: 14,104,850 (GRCm39) probably null Het
Rbm8a G A 3: 96,537,368 (GRCm39) probably benign Het
Relch T A 1: 105,620,004 (GRCm39) M353K probably benign Het
Ros1 A G 10: 51,977,990 (GRCm39) S1419P possibly damaging Het
Rps6ka5 C T 12: 100,564,144 (GRCm39) probably null Het
Rps6ka5 T A 12: 100,547,578 (GRCm39) I311F probably damaging Het
Rtel1 T C 2: 180,965,539 (GRCm39) probably null Het
Sacs A G 14: 61,441,722 (GRCm39) E1256G probably damaging Het
Sec23a A G 12: 59,029,372 (GRCm39) V467A probably damaging Het
Sec24d T A 3: 123,149,427 (GRCm39) N811K possibly damaging Het
Sf3b1 G A 1: 55,029,666 (GRCm39) T1112M probably damaging Het
Shisa5 T A 9: 108,885,128 (GRCm39) C133S probably null Het
Slc16a6 A G 11: 109,354,193 (GRCm39) S59P probably benign Het
Slc25a31 G A 3: 40,670,975 (GRCm39) A89T probably damaging Het
Slc6a1 G T 6: 114,284,713 (GRCm39) R257L possibly damaging Het
Sntb1 C T 15: 55,612,670 (GRCm39) V303M probably benign Het
Snx20 A G 8: 89,354,439 (GRCm39) V97A probably damaging Het
Vmn1r29 T A 6: 58,285,136 (GRCm39) N285K probably benign Het
Vmn2r98 T G 17: 19,290,007 (GRCm39) S514R probably damaging Het
Zfp28 A T 7: 6,392,793 (GRCm39) E156D probably damaging Het
Zfp536 A C 7: 37,268,891 (GRCm39) I175S probably damaging Het
Zic5 A T 14: 122,696,969 (GRCm39) S549T unknown Het
Other mutations in Zfp39
AlleleSourceChrCoordTypePredicted EffectPPH Score
IGL00791:Zfp39 APN 11 58,783,885 (GRCm39) splice site probably benign
IGL01597:Zfp39 APN 11 58,782,369 (GRCm39) missense probably damaging 0.96
IGL02055:Zfp39 APN 11 58,782,156 (GRCm39) missense probably benign
IGL02456:Zfp39 APN 11 58,793,626 (GRCm39) nonsense probably null
IGL02873:Zfp39 APN 11 58,781,848 (GRCm39) missense probably benign 0.12
H8562:Zfp39 UTSW 11 58,791,512 (GRCm39) missense probably damaging 1.00
R0462:Zfp39 UTSW 11 58,781,232 (GRCm39) missense probably benign 0.03
R0513:Zfp39 UTSW 11 58,780,813 (GRCm39) missense probably benign 0.09
R1185:Zfp39 UTSW 11 58,793,670 (GRCm39) missense possibly damaging 0.91
R1185:Zfp39 UTSW 11 58,793,670 (GRCm39) missense possibly damaging 0.91
R1185:Zfp39 UTSW 11 58,793,670 (GRCm39) missense possibly damaging 0.91
R1401:Zfp39 UTSW 11 58,781,149 (GRCm39) missense probably benign 0.01
R1797:Zfp39 UTSW 11 58,791,486 (GRCm39) missense probably damaging 0.96
R2146:Zfp39 UTSW 11 58,781,158 (GRCm39) missense probably benign 0.05
R3903:Zfp39 UTSW 11 58,781,001 (GRCm39) missense probably benign 0.44
R4303:Zfp39 UTSW 11 58,780,843 (GRCm39) missense probably damaging 1.00
R4957:Zfp39 UTSW 11 58,782,057 (GRCm39) missense possibly damaging 0.63
R5092:Zfp39 UTSW 11 58,782,028 (GRCm39) missense possibly damaging 0.71
R5158:Zfp39 UTSW 11 58,780,671 (GRCm39) missense possibly damaging 0.81
R5292:Zfp39 UTSW 11 58,791,415 (GRCm39) missense probably damaging 0.97
R5697:Zfp39 UTSW 11 58,780,661 (GRCm39) missense probably benign 0.08
R5906:Zfp39 UTSW 11 58,793,717 (GRCm39) missense probably benign
R5925:Zfp39 UTSW 11 58,782,099 (GRCm39) missense possibly damaging 0.94
R6174:Zfp39 UTSW 11 58,782,213 (GRCm39) missense probably benign 0.01
R6177:Zfp39 UTSW 11 58,781,887 (GRCm39) missense probably benign 0.27
R6968:Zfp39 UTSW 11 58,782,306 (GRCm39) missense probably benign 0.00
R7045:Zfp39 UTSW 11 58,781,269 (GRCm39) missense unknown
R7139:Zfp39 UTSW 11 58,781,385 (GRCm39) missense probably damaging 1.00
R7421:Zfp39 UTSW 11 58,780,933 (GRCm39) missense probably damaging 1.00
R7493:Zfp39 UTSW 11 58,781,869 (GRCm39) missense possibly damaging 0.82
R7689:Zfp39 UTSW 11 58,781,469 (GRCm39) missense probably damaging 1.00
R8061:Zfp39 UTSW 11 58,793,573 (GRCm39) missense probably benign
R8136:Zfp39 UTSW 11 58,782,228 (GRCm39) missense probably damaging 0.99
R8955:Zfp39 UTSW 11 58,780,946 (GRCm39) nonsense probably null
Z1186:Zfp39 UTSW 11 58,781,724 (GRCm39) missense probably benign 0.01
Z1186:Zfp39 UTSW 11 58,781,751 (GRCm39) missense probably benign 0.29
Z1186:Zfp39 UTSW 11 58,781,967 (GRCm39) missense probably damaging 0.99
Z1186:Zfp39 UTSW 11 58,782,123 (GRCm39) missense probably benign
Z1186:Zfp39 UTSW 11 58,782,142 (GRCm39) missense probably benign
Z1186:Zfp39 UTSW 11 58,791,407 (GRCm39) missense probably benign 0.01
Z1186:Zfp39 UTSW 11 58,791,409 (GRCm39) missense probably benign 0.01
Z1186:Zfp39 UTSW 11 58,780,871 (GRCm39) nonsense probably null
Z1186:Zfp39 UTSW 11 58,780,873 (GRCm39) missense probably benign 0.01
Z1186:Zfp39 UTSW 11 58,781,130 (GRCm39) missense possibly damaging 0.91
Z1186:Zfp39 UTSW 11 58,781,273 (GRCm39) missense probably benign 0.16
Z1186:Zfp39 UTSW 11 58,781,274 (GRCm39) missense possibly damaging 0.86
Z1186:Zfp39 UTSW 11 58,781,526 (GRCm39) missense possibly damaging 0.50
Z1186:Zfp39 UTSW 11 58,781,597 (GRCm39) missense probably benign 0.00
Z1186:Zfp39 UTSW 11 58,781,605 (GRCm39) missense probably benign 0.09
Z1187:Zfp39 UTSW 11 58,781,605 (GRCm39) missense probably benign 0.09
Z1187:Zfp39 UTSW 11 58,781,597 (GRCm39) missense probably benign 0.00
Z1187:Zfp39 UTSW 11 58,781,526 (GRCm39) missense possibly damaging 0.50
Z1187:Zfp39 UTSW 11 58,781,274 (GRCm39) missense possibly damaging 0.86
Z1187:Zfp39 UTSW 11 58,781,273 (GRCm39) missense probably benign 0.16
Z1187:Zfp39 UTSW 11 58,781,130 (GRCm39) missense possibly damaging 0.91
Z1187:Zfp39 UTSW 11 58,780,873 (GRCm39) missense probably benign 0.01
Z1187:Zfp39 UTSW 11 58,780,871 (GRCm39) nonsense probably null
Z1187:Zfp39 UTSW 11 58,791,409 (GRCm39) missense probably benign 0.01
Z1187:Zfp39 UTSW 11 58,791,407 (GRCm39) missense probably benign 0.01
Z1187:Zfp39 UTSW 11 58,782,142 (GRCm39) missense probably benign
Z1187:Zfp39 UTSW 11 58,782,123 (GRCm39) missense probably benign
Z1187:Zfp39 UTSW 11 58,781,967 (GRCm39) missense probably damaging 0.99
Z1187:Zfp39 UTSW 11 58,781,751 (GRCm39) missense probably benign 0.29
Z1187:Zfp39 UTSW 11 58,781,724 (GRCm39) missense probably benign 0.01
Z1187:Zfp39 UTSW 11 58,781,712 (GRCm39) missense probably benign 0.01
Z1187:Zfp39 UTSW 11 58,781,702 (GRCm39) missense probably damaging 0.97
Z1188:Zfp39 UTSW 11 58,781,967 (GRCm39) missense probably damaging 0.99
Z1188:Zfp39 UTSW 11 58,781,751 (GRCm39) missense probably benign 0.29
Z1188:Zfp39 UTSW 11 58,781,724 (GRCm39) missense probably benign 0.01
Z1188:Zfp39 UTSW 11 58,781,712 (GRCm39) missense probably benign 0.01
Z1188:Zfp39 UTSW 11 58,781,702 (GRCm39) missense probably damaging 0.97
Z1188:Zfp39 UTSW 11 58,782,123 (GRCm39) missense probably benign
Z1188:Zfp39 UTSW 11 58,782,142 (GRCm39) missense probably benign
Z1188:Zfp39 UTSW 11 58,791,407 (GRCm39) missense probably benign 0.01
Z1188:Zfp39 UTSW 11 58,791,409 (GRCm39) missense probably benign 0.01
Z1188:Zfp39 UTSW 11 58,780,871 (GRCm39) nonsense probably null
Z1188:Zfp39 UTSW 11 58,780,873 (GRCm39) missense probably benign 0.01
Z1188:Zfp39 UTSW 11 58,781,130 (GRCm39) missense possibly damaging 0.91
Z1188:Zfp39 UTSW 11 58,781,273 (GRCm39) missense probably benign 0.16
Z1188:Zfp39 UTSW 11 58,781,274 (GRCm39) missense possibly damaging 0.86
Z1188:Zfp39 UTSW 11 58,781,526 (GRCm39) missense possibly damaging 0.50
Z1188:Zfp39 UTSW 11 58,781,597 (GRCm39) missense probably benign 0.00
Z1188:Zfp39 UTSW 11 58,781,605 (GRCm39) missense probably benign 0.09
Z1189:Zfp39 UTSW 11 58,781,597 (GRCm39) missense probably benign 0.00
Z1189:Zfp39 UTSW 11 58,781,526 (GRCm39) missense possibly damaging 0.50
Z1189:Zfp39 UTSW 11 58,781,274 (GRCm39) missense possibly damaging 0.86
Z1189:Zfp39 UTSW 11 58,781,273 (GRCm39) missense probably benign 0.16
Z1189:Zfp39 UTSW 11 58,781,130 (GRCm39) missense possibly damaging 0.91
Z1189:Zfp39 UTSW 11 58,780,873 (GRCm39) missense probably benign 0.01
Z1189:Zfp39 UTSW 11 58,780,871 (GRCm39) nonsense probably null
Z1189:Zfp39 UTSW 11 58,791,409 (GRCm39) missense probably benign 0.01
Z1189:Zfp39 UTSW 11 58,791,407 (GRCm39) missense probably benign 0.01
Z1189:Zfp39 UTSW 11 58,782,142 (GRCm39) missense probably benign
Z1189:Zfp39 UTSW 11 58,782,123 (GRCm39) missense probably benign
Z1189:Zfp39 UTSW 11 58,781,967 (GRCm39) missense probably damaging 0.99
Z1189:Zfp39 UTSW 11 58,781,751 (GRCm39) missense probably benign 0.29
Z1189:Zfp39 UTSW 11 58,781,605 (GRCm39) missense probably benign 0.09
Z1190:Zfp39 UTSW 11 58,781,702 (GRCm39) missense probably damaging 0.97
Z1190:Zfp39 UTSW 11 58,781,724 (GRCm39) missense probably benign 0.01
Z1190:Zfp39 UTSW 11 58,781,751 (GRCm39) missense probably benign 0.29
Z1190:Zfp39 UTSW 11 58,781,967 (GRCm39) missense probably damaging 0.99
Z1190:Zfp39 UTSW 11 58,782,123 (GRCm39) missense probably benign
Z1190:Zfp39 UTSW 11 58,782,142 (GRCm39) missense probably benign
Z1190:Zfp39 UTSW 11 58,791,407 (GRCm39) missense probably benign 0.01
Z1190:Zfp39 UTSW 11 58,791,409 (GRCm39) missense probably benign 0.01
Z1190:Zfp39 UTSW 11 58,780,871 (GRCm39) nonsense probably null
Z1190:Zfp39 UTSW 11 58,780,873 (GRCm39) missense probably benign 0.01
Z1190:Zfp39 UTSW 11 58,781,130 (GRCm39) missense possibly damaging 0.91
Z1190:Zfp39 UTSW 11 58,781,273 (GRCm39) missense probably benign 0.16
Z1190:Zfp39 UTSW 11 58,781,274 (GRCm39) missense possibly damaging 0.86
Z1190:Zfp39 UTSW 11 58,781,526 (GRCm39) missense possibly damaging 0.50
Z1190:Zfp39 UTSW 11 58,781,597 (GRCm39) missense probably benign 0.00
Z1190:Zfp39 UTSW 11 58,781,605 (GRCm39) missense probably benign 0.09
Z1191:Zfp39 UTSW 11 58,781,605 (GRCm39) missense probably benign 0.09
Z1191:Zfp39 UTSW 11 58,781,597 (GRCm39) missense probably benign 0.00
Z1191:Zfp39 UTSW 11 58,781,526 (GRCm39) missense possibly damaging 0.50
Z1191:Zfp39 UTSW 11 58,781,274 (GRCm39) missense possibly damaging 0.86
Z1191:Zfp39 UTSW 11 58,781,273 (GRCm39) missense probably benign 0.16
Z1191:Zfp39 UTSW 11 58,781,130 (GRCm39) missense possibly damaging 0.91
Z1191:Zfp39 UTSW 11 58,780,873 (GRCm39) missense probably benign 0.01
Z1191:Zfp39 UTSW 11 58,780,871 (GRCm39) nonsense probably null
Z1191:Zfp39 UTSW 11 58,791,409 (GRCm39) missense probably benign 0.01
Z1191:Zfp39 UTSW 11 58,791,407 (GRCm39) missense probably benign 0.01
Z1191:Zfp39 UTSW 11 58,782,142 (GRCm39) missense probably benign
Z1191:Zfp39 UTSW 11 58,782,123 (GRCm39) missense probably benign
Z1191:Zfp39 UTSW 11 58,781,967 (GRCm39) missense probably damaging 0.99
Z1191:Zfp39 UTSW 11 58,781,751 (GRCm39) missense probably benign 0.29
Z1191:Zfp39 UTSW 11 58,781,724 (GRCm39) missense probably benign 0.01
Z1191:Zfp39 UTSW 11 58,781,712 (GRCm39) missense probably benign 0.01
Z1191:Zfp39 UTSW 11 58,781,702 (GRCm39) missense probably damaging 0.97
Z1192:Zfp39 UTSW 11 58,781,605 (GRCm39) missense probably benign 0.09
Z1192:Zfp39 UTSW 11 58,781,597 (GRCm39) missense probably benign 0.00
Z1192:Zfp39 UTSW 11 58,781,526 (GRCm39) missense possibly damaging 0.50
Z1192:Zfp39 UTSW 11 58,781,274 (GRCm39) missense possibly damaging 0.86
Z1192:Zfp39 UTSW 11 58,781,273 (GRCm39) missense probably benign 0.16
Z1192:Zfp39 UTSW 11 58,781,130 (GRCm39) missense possibly damaging 0.91
Z1192:Zfp39 UTSW 11 58,780,873 (GRCm39) missense probably benign 0.01
Z1192:Zfp39 UTSW 11 58,780,871 (GRCm39) nonsense probably null
Z1192:Zfp39 UTSW 11 58,791,409 (GRCm39) missense probably benign 0.01
Z1192:Zfp39 UTSW 11 58,791,407 (GRCm39) missense probably benign 0.01
Z1192:Zfp39 UTSW 11 58,782,142 (GRCm39) missense probably benign
Z1192:Zfp39 UTSW 11 58,782,123 (GRCm39) missense probably benign
Z1192:Zfp39 UTSW 11 58,781,967 (GRCm39) missense probably damaging 0.99
Z1192:Zfp39 UTSW 11 58,781,751 (GRCm39) missense probably benign 0.29
Z1192:Zfp39 UTSW 11 58,781,724 (GRCm39) missense probably benign 0.01
Predicted Primers PCR Primer
(F):5'- ACAAGCACAATGTTGTATCTCTCC -3'
(R):5'- TGACAGTGACTCCTTTGCTG -3'

Sequencing Primer
(F):5'- ATCTAACTCAGGTCGTCAGGACTG -3'
(R):5'- CCTTTGCTGGAGACGAGAG -3'
Posted On 2015-10-21