12-8604926-CAAAAAAAAA-CAAAAAAA

Variant names:

• chr12-8604926-CAA-C
• rs5796316
• NM_020661.4:c.428-6_428-5delTT

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_020661.4(AICDA):​c.428-6_428-5delTT variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000137 in 1,386,126 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.000015 (0 hom., cov: 0)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: AICDA NM_020661.4 splice_region, intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.941

Genes affected

AICDA (HGNC:13203): (activation induced cytidine deaminase) This gene encodes a RNA-editing deaminase that is a member of the cytidine deaminase family. AICDA is specifically expressed and active in germinal center-like B cells. In the germinal center, AICDA is involved in somatic hypermutation, gene conversion, and class-switch recombination of immunoglobulin genes. An epigenetic role in neoplastic transformation and lymphoma progression has been experimentally ascribed to AICDA using mouse models. Defects in this gene are the cause of autosomal recessive hyper-IgM immunodeficiency syndrome type 2 (HIGM2). [provided by RefSeq, Jul 2020]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
AICDA	NM_020661.4	c.428-6_428-5delTT		splice_region_variant, intron_variant	Intron 3 of 4	ENST00000229335.11	NP_065712.1
AICDA	NM_001330343.2	c.428-36_428-35delTT		intron_variant	Intron 3 of 4		NP_001317272.1
AICDA	NM_001410970.1	c.427+287_427+288delTT		intron_variant	Intron 3 of 3		NP_001397899.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
AICDA	ENST00000229335.11	c.428-6_428-5delTT		splice_region_variant, intron_variant	Intron 3 of 4	1	NM_020661.4	ENSP00000229335.6

Frequencies

GnomAD3 genomes AF: 0.0000146 AC: 2 AN: 136834 Hom.: 0 Cov.: 0

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.000304

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000136 AC: 17 AN: 1249296 Hom.: 0 AF XY: 0.0000128 AC XY: 8 AN XY: 622698

Gnomad4 AFR exome AF: 0.000103

Gnomad4 AMR exome AF: 0.000182

Gnomad4 ASJ exome AF: 0.0000449

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000271

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000521

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000146 AC: 2 AN: 136830 Hom.: 0 Cov.: 0 AF XY: 0.0000305 AC XY: 2 AN XY: 65522

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.000304

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs5796316; hg19: chr12-8757522;