16-10915623-C-T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBS1_Supporting

The NM_000246.4(CIITA):​c.2942C>T​(p.Thr981Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000062 in 1,614,122 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T981A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00014 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000054 ( 0 hom. )

Consequence

CIITA
NM_000246.4 missense

Scores

17

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.989

Publications

4 publications found
Variant links:
Genes affected
CIITA (HGNC:7067): (class II major histocompatibility complex transactivator) This gene encodes a protein with an acidic transcriptional activation domain, 4 LRRs (leucine-rich repeats) and a GTP binding domain. The protein is located in the nucleus and acts as a positive regulator of class II major histocompatibility complex gene transcription, and is referred to as the "master control factor" for the expression of these genes. The protein also binds GTP and uses GTP binding to facilitate its own transport into the nucleus. Once in the nucleus it does not bind DNA but rather uses an intrinsic acetyltransferase (AT) activity to act in a coactivator-like fashion. Mutations in this gene have been associated with bare lymphocyte syndrome type II (also known as hereditary MHC class II deficiency or HLA class II-deficient combined immunodeficiency), increased susceptibility to rheumatoid arthritis, multiple sclerosis, and possibly myocardial infarction. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2013]
CIITA Gene-Disease associations (from GenCC):
  • MHC class II deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.032827318).
BS1
Variant frequency is greater than expected in population amr. GnomAd4 allele frequency = 0.000138 (21/152316) while in subpopulation AMR AF = 0.000915 (14/15302). AF 95% confidence interval is 0.000553. There are 0 homozygotes in GnomAd4. There are 15 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CIITANM_000246.4 linkc.2942C>T p.Thr981Met missense_variant Exon 14 of 20 ENST00000324288.14 NP_000237.2 P33076A0A0B4J1S1Q66X48

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CIITAENST00000324288.14 linkc.2942C>T p.Thr981Met missense_variant Exon 14 of 20 1 NM_000246.4 ENSP00000316328.8 A0A0B4J1S1

Frequencies

GnomAD3 genomes
AF:
0.000138
AC:
21
AN:
152198
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000916
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.000957
GnomAD2 exomes
AF:
0.000135
AC:
34
AN:
251432
AF XY:
0.000118
show subpopulations
Gnomad AFR exome
AF:
0.000123
Gnomad AMR exome
AF:
0.000491
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.0000463
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.000652
GnomAD4 exome
AF:
0.0000540
AC:
79
AN:
1461806
Hom.:
0
Cov.:
31
AF XY:
0.0000660
AC XY:
48
AN XY:
727212
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000447
AC:
20
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.000255
AC:
22
AN:
86256
European-Finnish (FIN)
AF:
0.0000375
AC:
2
AN:
53386
Middle Eastern (MID)
AF:
0.000520
AC:
3
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000243
AC:
27
AN:
1111966
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
5
10
15
20
25
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000138
AC:
21
AN:
152316
Hom.:
0
Cov.:
32
AF XY:
0.000201
AC XY:
15
AN XY:
74490
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41564
American (AMR)
AF:
0.000915
AC:
14
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68022
Other (OTH)
AF:
0.000947
AC:
2
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.513
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000494
Hom.:
0
Bravo
AF:
0.0000982
ESP6500AA
AF:
0.000228
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000115
AC:
14
EpiCase
AF:
0.000109
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

MHC class II deficiency Uncertain:1
Sep 06, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 981 of the CIITA protein (p.Thr981Met). This variant is present in population databases (rs369744959, gnomAD 0.05%). This variant has not been reported in the literature in individuals affected with CIITA-related conditions. ClinVar contains an entry for this variant (Variation ID: 568716). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The methionine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.076
BayesDel_addAF
Benign
-0.46
T
BayesDel_noAF
Benign
-0.57
CADD
Benign
17
DANN
Benign
0.97
Eigen
Benign
-0.80
Eigen_PC
Benign
-0.84
FATHMM_MKL
Benign
0.10
N
LIST_S2
Benign
0.66
T;T;T
M_CAP
Benign
0.026
D
MetaRNN
Benign
0.033
T;T;T
MetaSVM
Benign
-1.1
T
PhyloP100
0.99
PrimateAI
Benign
0.30
T
PROVEAN
Benign
-0.99
.;N;N
REVEL
Benign
0.048
Sift
Benign
0.037
.;D;T
Sift4G
Benign
0.11
T;T;T
Vest4
0.082
MVP
0.59
MPC
0.13
ClinPred
0.016
T
GERP RS
2.6
gMVP
0.32
Mutation Taster
=92/8
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.080
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs369744959; hg19: chr16-11009480; COSMIC: COSV60862667; COSMIC: COSV60862667; API