2-73602289-G-T

Variant names:

• chr2-73602289-G-T
• rs878854996
• NM_001378454.1:c.12219G>T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_001378454.1(ALMS1):​c.12219G>T​(p.Gln4073His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts 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. Q4073K) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ALMS1 NM_001378454.1 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 1.87
• 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 Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, PanelApp Australia, G2P, Orphanet, Genomics England PanelApp

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.30414897).

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALMS1	NM_001378454.1	MANE Select	c.12219G>T	p.Gln4073His	missense	Exon 20 of 23	NP_001365383.1
	ALMS1	NM_015120.4		c.12219G>T	p.Gln4073His	missense	Exon 20 of 23	NP_055935.4

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALMS1	ENST00000613296.6	TSL:1 MANE Select	c.12219G>T	p.Gln4073His	missense	Exon 20 of 23	ENSP00000482968.1
	ALMS1	ENST00000484298.5	TSL:1	c.12093G>T	p.Gln4031His	missense	Exon 19 of 22	ENSP00000478155.1
	ALMS1	ENST00000684548.1		c.11838G>T	p.Gln3946His	missense	Exon 18 of 21	ENSP00000507421.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000370 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Alstrom syndrome Uncertain:2

Jul 06, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamine, which is neutral and polar, with histidine, which is basic and polar, at codon 4074 of the ALMS1 protein (p.Gln4074His). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ALMS1-related conditions. ClinVar contains an entry for this variant (Variation ID: 240981). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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.

Jan 24, 2018

Counsyl

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com.

not provided Uncertain:1

Feb 29, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.48
BayesDel_addAF	Uncertain	0.050	T
BayesDel_noAF	Benign	-0.17
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Benign	0.13	T
Eigen	Benign	0.14
Eigen_PC	Benign	0.028
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Benign	0.76	T
M_CAP	Benign	0.0021	T
MetaRNN	Benign	0.30	T
MetaSVM	Benign	-1.2	T
PhyloP100		1.9
PrimateAI	Benign	0.43	T
Sift4G	Uncertain	0.0030	D
Vest4		0.40
MVP		0.32
ClinPred		0.88	D
GERP RS		2.4
Varity_R		0.033
gMVP		0.27
Mutation Taster		=77/23	polymorphism

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: rs878854996; hg19: chr2-73829416;