chr2-73451700-G-GC

Variant names:

• chr2-73451700-G-GC
• rs1553404020
• NM_001378454.1:c.5176dupC

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001378454.1(ALMS1):​c.5176dupC​(p.Leu1726ProfsTer5) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. L1726L) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ALMS1 NM_001378454.1 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3 U:1
• Conservation: PhyloP100: -6.40
• Publications: 0 publications found

Genes affected

ALMS1 (HGNC:428): (ALMS1 centrosome and basal body associated protein) This gene encodes a protein containing a large tandem-repeat domain as well as additional low complexity regions. The encoded protein functions in microtubule organization, particularly in the formation and maintanance of cilia. Mutations in this gene cause Alstrom syndrome. There is a pseudogene for this gene located adjacent in the same region of chromosome 2. Alternative splice variants have been described but their full length nature has not been determined. [provided by RefSeq, Apr 2014]

ALMS1 Gene-Disease associations (from GenCC):

• Alstrom syndrome

  Inheritance: AR, Unknown Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-73451700-G-GC is Pathogenic according to our data. Variant chr2-73451700-G-GC is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 553501.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001378454.1. 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
	ALMS1	NM_001378454.1	MANE Select	c.5176dupC	p.Leu1726ProfsTer5	frameshift	Exon 8 of 23	NP_001365383.1	Q8TCU4-1
	ALMS1	NM_015120.4		c.5176dupC	p.Leu1726ProfsTer5	frameshift	Exon 8 of 23	NP_055935.4	Q8TCU4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALMS1	ENST00000613296.6	TSL:1 MANE Select	c.5176dupC	p.Leu1726ProfsTer5	frameshift	Exon 8 of 23	ENSP00000482968.1	Q8TCU4-1
	ALMS1	ENST00000484298.5	TSL:1	c.5050dupC	p.Leu1684ProfsTer5	frameshift	Exon 7 of 22	ENSP00000478155.1	A0A087WTU9
	ALMS1	ENST00000423048.5	TSL:1	n.7dupC		non_coding_transcript_exon	Exon 1 of 9	ENSP00000399833.1	H7C1D9

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 39

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	Alstrom syndrome (3)
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		-6.4
Mutation Taster		=0/200	disease causing (ClinVar)

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

dbSNP: rs1553404020; hg19: chr2-73678827;