rs75521576

chr16-10922428-G-Achr16-10922428-G-T

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_Strong BP6_Very_Strong BP7 BS1 BS2

The NM_000246.4(CIITA):c.3255G>A(p.Thr1085=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00166 in 1,614,214 control chromosomes in the GnomAD database, including 47 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0087 (25 hom., cov: 33)
  • Exomes 𝑓: 0.00092 (22 hom.)
• Consequence: CIITA NM_000246.4 synonymous
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: -1.51

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]

ACMG classification

Verdict is Benign. Variant got -21 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.57).
• BP6: Variant 16-10922428-G-A is Benign according to our data. Variant chr16-10922428-G-A is described in ClinVar as [Benign]. Clinvar id is 317726.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=-1.51 with no splicing effect.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00874 (1331/152352) while in subpopulation AFR AF= 0.0303 (1262/41582). AF 95% confidence interval is 0.029. There are 25 homozygotes in gnomad4. There are 641 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High Homozygotes in GnomAd at 25 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CIITA	NM_000246.4	c.3255G>A	p.Thr1085=	synonymous_variant	18/20	ENST00000324288.14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CIITA	ENST00000324288.14	c.3255G>A	p.Thr1085=	synonymous_variant	18/20	1	NM_000246.4	P4

Frequencies

GnomAD3 genomes AF: 0.00873 AC: 1329 AN: 152234 Hom.: 25 Cov.: 33

Gnomad AFR AF: 0.0304

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00268

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000769

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000882

Gnomad OTH AF: 0.00860

GnomAD3 exomes AF: 0.00233 AC: 584 AN: 251118 Hom.: 8 AF XY: 0.00168 AC XY: 228 AN XY: 135796

Gnomad AFR exome AF: 0.0316

Gnomad AMR exome AF: 0.00168

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000435

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000264

Gnomad OTH exome AF: 0.000653

GnomAD4 exome AF: 0.000921 AC: 1346 AN: 1461862 Hom.: 22 Cov.: 32 AF XY: 0.000780 AC XY: 567 AN XY: 727236

Gnomad4 AFR exome AF: 0.0326

Gnomad4 AMR exome AF: 0.00188

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000756

Gnomad4 SAS exome AF: 0.000104

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000315

Gnomad4 OTH exome AF: 0.00199

GnomAD4 genome AF: 0.00874 AC: 1331 AN: 152352 Hom.: 25 Cov.: 33 AF XY: 0.00860 AC XY: 641 AN XY: 74508

Gnomad4 AFR AF: 0.0303

Gnomad4 AMR AF: 0.00268

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000771

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000882

Gnomad4 OTH AF: 0.00851

Alfa AF: 0.00409 Hom.: 3

Bravo AF: 0.0104

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

MHC class II deficiency Benign:3

Benign, criteria provided, single submitter	clinical testing	Invitae	Jan 31, 2024	- -
Benign, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.57
Cadd	Benign	1.8
Dann	Benign	0.86

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs75521576; hg19: chr16-11016285;