chr22-24302301-G-GA

Variant names:

• chr22-24302301-G-GA
• NM_015330.6:c.76dupA

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_015330.6(SPECC1L):​c.76dupA​(p.Ile26AsnfsTer2) variant causes a frameshift change. The variant allele was found at a frequency of 0.000000684 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SPECC1L NM_015330.6 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.09
• Publications: 0 publications found

Genes affected

SPECC1L (HGNC:29022): (sperm antigen with calponin homology and coiled-coil domains 1 like) This gene encodes a coiled-coil domain containing protein. The encoded protein may play a critical role in actin-cytoskeletal reorganization during facial morphogenesis. Mutations in this gene are a cause of oblique facial clefting-1. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. A read-through transcript composed of SPECC1L (sperm antigen with calponin homology and coiled-coil domains 1-like) and the downstream ADORA2A (adenosine A2a receptor) gene sequence has been identified, but it is thought to be non-coding. [provided by RefSeq, Jun 2013]

SPECC1L-ADORA2A (HGNC:49185): (SPECC1L-ADORA2A readthrough (NMD candidate)) This locus represents naturally occurring readthrough transcription between the neighboring SPECC1L (sperm antigen with calponin homology and coiled-coil domains 1-like) and ADORA2A (adenosine A2a receptor) genes on chromosome 22. The readthrough transcript is a candidate for nonsense-mediated mRNA decay (NMD) and is unlikely to produce a protein product. [provided by RefSeq, Jun 2013]

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 18 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_015330.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SPECC1L	NM_015330.6	MANE Select	c.76dupA	p.Ile26AsnfsTer2	frameshift	Exon 3 of 17	NP_056145.5	Q69YQ0-1
	SPECC1L	NM_001145468.4		c.76dupA	p.Ile26AsnfsTer2	frameshift	Exon 2 of 16	NP_001138940.4	Q69YQ0-1
	SPECC1L	NM_001254732.3		c.76dupA	p.Ile26AsnfsTer2	frameshift	Exon 2 of 15	NP_001241661.3	Q69YQ0-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SPECC1L	ENST00000314328.14	TSL:1 MANE Select	c.76dupA	p.Ile26AsnfsTer2	frameshift	Exon 3 of 17	ENSP00000325785.8	Q69YQ0-1
	SPECC1L	ENST00000437398.5	TSL:1	c.76dupA	p.Ile26AsnfsTer2	frameshift	Exon 2 of 16	ENSP00000393363.1	Q69YQ0-1
	SPECC1L-ADORA2A	ENST00000358654.2	TSL:2	n.76dupA		non_coding_transcript_exon	Exon 3 of 20	ENSP00000351480.2	F8WAN1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461880 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727240

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112008

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		4.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

hg19: chr22-24698269;