chr1-225422279-T-C

Variant names:

• chr1-225422279-T-C
• rs886037617
• NM_002296.4:c.166-2A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PVS1_Strong PM2 PP5

The NM_002296.4(LBR):​c.166-2A>G variant causes a splice acceptor, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: LBR NM_002296.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 5.29
• Publications: 0 publications found

Genes affected

LBR (HGNC:6518): (lamin B receptor) The protein encoded by this gene belongs to the ERG4/ERG24 family. It localized in the nuclear envelope inner membrane and anchors the lamina and the heterochromatin to the membrane. It may mediate interaction between chromatin and lamin B. Mutations of this gene has been associated with autosomal recessive HEM/Greenberg skeletal dysplasia. Alternative splicing occurs at this locus and two transcript variants encoding the same protein have been identified. [provided by RefSeq, Jul 2008]

LBR Gene-Disease associations (from GenCC):

• Greenberg dysplasia

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae), ClinGen, G2P
• Pelger-Huet anomaly

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• regressive spondylometaphyseal dysplasia

  Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.108766235 fraction of the gene. Cryptic splice site detected, with MaxEntScore 7.9, offset of 17, new splice context is: tggcctttaacttcctttAGgca. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-225422279-T-C is Pathogenic according to our data. Variant chr1-225422279-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 9528.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002296.4. 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
	LBR	NM_002296.4	MANE Select	c.166-2A>G		splice_acceptor intron	N/A	NP_002287.2
	LBR	NM_194442.3		c.166-2A>G		splice_acceptor intron	N/A	NP_919424.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LBR	ENST00000272163.9	TSL:1 MANE Select	c.166-2A>G		splice_acceptor intron	N/A	ENSP00000272163.4
	LBR	ENST00000488632.1	TSL:3	n.149A>G		non_coding_transcript_exon	Exon 1 of 2
	LBR	ENST00000338179.6	TSL:5	c.166-2A>G		splice_acceptor intron	N/A	ENSP00000339883.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Pelger-Huët anomaly (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	32
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Uncertain	0.93	D
PhyloP100		5.3
GERP RS		6.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.1
Mutation Taster		=3/97	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.96		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.96		Position offset: -2

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

Other links and lift over

dbSNP: rs886037617; hg19: chr1-225609981;