rs1554705383

Positions:

• chr9-92718723-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM2 PM5 PP2 PP3_Strong

The NM_001003800.2(BICD2):​c.1922T>C​(p.Leu641Pro) 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. 13/21 in silico tools predict a damaging 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. L641R) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: BICD2 NM_001003800.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.16

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 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-T is described in ClinVar as [Pathogenic]. Clinvar id is 2865170.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), BICD2. . Gene score misZ 2.205 (greater than the threshold 3.09). Trascript score misZ 3.1082 (greater than threshold 3.09). GenCC has associacion of gene with autosomal dominant childhood-onset proximal spinal muscular atrophy with contractures.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.98

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BICD2	NM_001003800.2	c.1922T>C	p.Leu641Pro	missense_variant	5/7	ENST00000356884.11
BICD2	NM_015250.4	c.1922T>C	p.Leu641Pro	missense_variant	5/8
BICD2	XM_017014551.2	c.2003T>C	p.Leu668Pro	missense_variant	5/8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BICD2	ENST00000356884.11	c.1922T>C	p.Leu641Pro	missense_variant	5/7	1	NM_001003800.2	A2
BICD2	ENST00000375512.3	c.1922T>C	p.Leu641Pro	missense_variant	5/8	1		P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 01, 2023

This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 641 of the BICD2 protein (p.Leu641Pro). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with BICD2-related conditions. ClinVar contains an entry for this variant (Variation ID: 541282). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt BICD2 protein function with a positive predictive value of 80%. 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. -

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	32
DANN	Pathogenic	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	0.61	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Uncertain	0.024	D
MutationAssessor	Pathogenic	3.5	M;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-6.7	D;D
REVEL	Pathogenic	0.79
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;D
Vest4		0.96
MutPred		0.88		Gain of disorder (P = 0.0169);Gain of disorder (P = 0.0169);
MVP		0.91
MPC		1.9
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.96
gMVP		0.98

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

Publications

LitVar

Other links and lift over

dbSNP: rs1554705383; hg19: chr9-95481005;