9-92718723-A-T

Variant names:

• chr9-92718723-A-T
• rs1554705383
• NM_001003800.2:c.1922T>A

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM2 PM5 PP3_Strong PP5_Moderate

The NM_001003800.2(BICD2):​c.1922T>A​(p.Leu641Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L641R) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: BICD2 NM_001003800.2 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.16
• Publications: 0 publications found

Genes affected

BICD2 (HGNC:17208): (BICD cargo adaptor 2) This gene is one of two human homologs of Drosophila bicaudal-D and a member of the Bicoid family. It has been implicated in dynein-mediated, minus end-directed motility along microtubules. It has also been reported to be a phosphorylation target of NIMA related kinase 8. Two alternative splice variants have been described. [provided by RefSeq, Jul 2008]

BICD2 Gene-Disease associations (from GenCC):

• autosomal dominant childhood-onset proximal spinal muscular atrophy with contractures

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

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr9-92718723-A-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2442262.Status of the report is no_assertion_criteria_provided, 0 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.97
• PP5: Variant 9-92718723-A-T is Pathogenic according to our data. Variant chr9-92718723-A-T is described in ClinVar as Pathogenic. ClinVar VariationId is 2865170.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BICD2	NM_001003800.2	c.1922T>A	p.Leu641Gln	missense_variant	Exon 5 of 7	ENST00000356884.11	NP_001003800.1
BICD2	NM_015250.4	c.1922T>A	p.Leu641Gln	missense_variant	Exon 5 of 8		NP_056065.1
BICD2	XM_017014551.2	c.2003T>A	p.Leu668Gln	missense_variant	Exon 5 of 8		XP_016870040.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BICD2	ENST00000356884.11	c.1922T>A	p.Leu641Gln	missense_variant	Exon 5 of 7	1	NM_001003800.2	ENSP00000349351.6
BICD2	ENST00000375512.3	c.1922T>A	p.Leu641Gln	missense_variant	Exon 5 of 8	1		ENSP00000364662.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Autosomal dominant childhood-onset proximal spinal muscular atrophy with contractures Pathogenic:1

Oct 15, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with glutamine, which is neutral and polar, at codon 641 of the BICD2 protein (p.Leu641Gln). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of BICD2-related conditions (internal data). In at least one individual the variant was observed to be de novo. Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt BICD2 protein function with a positive predictive value of 80%. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.31
CADD	Pathogenic	31
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.86	.;D
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	1.0	D;D
M_CAP	Pathogenic	0.58	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Uncertain	0.024	D
MutationAssessor	Pathogenic	3.5	M;M
PhyloP100		9.2
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-5.8	D;D
REVEL	Pathogenic	0.79
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;D
Vest4		0.94
MutPred		0.85		Gain of disorder (P = 0.0194);Gain of disorder (P = 0.0194);
MVP		0.90
MPC		1.5
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.91
gMVP		0.94
Mutation Taster		=21/79	disease causing

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: rs1554705383; hg19: chr9-95481005;