7-66995354-G-A

Position:

• chr7-66995354-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_016038.4(SBDS):​c.64C>T​(p.Arg22Cys) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: SBDS NM_016038.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.40

Genes affected

SBDS (HGNC:19440): (SBDS ribosome maturation factor) This gene encodes a highly conserved protein that plays an essential role in ribosome biogenesis. The encoded protein interacts with elongation factor-like GTPase 1 to disassociate eukaryotic initiation factor 6 from the late cytoplasmic pre-60S ribosomal subunit allowing assembly of the 80S subunit. Mutations within this gene are associated with the autosomal recessive disorder Shwachman-Bodian-Diamond syndrome. This gene has a closely linked pseudogene that is distally located. [provided by RefSeq, Jan 2017]

TYW1 (HGNC:25598): (tRNA-yW synthesizing protein 1 homolog) Wybutosine (yW) is a hypermodified guanosine found in phenylalanine tRNA adjacent to the anticodon that stabilizes codon-anticodon interactions in the ribosome. In yeast, the homolog of this gene is essential for the synthesis of wybutosine. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2015]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a chain Ribosome maturation protein SBDS (size 248) in uniprot entity SBDS_HUMAN there are 4 pathogenic changes around while only 1 benign (80%) in NM_016038.4
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SBDS	NM_016038.4	c.64C>T	p.Arg22Cys	missense_variant	1/5	ENST00000246868.7	NP_057122.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SBDS	ENST00000246868.7	c.64C>T	p.Arg22Cys	missense_variant	1/5	1	NM_016038.4	ENSP00000246868.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 28, 2024

The p.R22C variant (also known as c.64C>T), located in coding exon 1 of the SBDS gene, results from a C to T substitution at nucleotide position 64. The arginine at codon 22 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.69
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.0
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.85	D;T
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.51
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Pathogenic	1.0	D;D
M_CAP	Pathogenic	0.65	D
MetaRNN	Uncertain	0.72	D;D
MetaSVM	Pathogenic	0.83	D
MutationAssessor	Uncertain	2.2	M;.
PrimateAI	Pathogenic	0.86	D
PROVEAN	Pathogenic	-5.2	D;.
REVEL	Pathogenic	0.69
Sift	Pathogenic	0.0	D;.
Sift4G	Pathogenic	0.0	D;D
Polyphen		0.99	D;.
Vest4		0.39
MutPred		0.55		Gain of catalytic residue at M20 (P = 0.0149);Gain of catalytic residue at M20 (P = 0.0149);
MVP		0.96
MPC		1.4
ClinPred		1.0	D
GERP RS		4.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.83
gMVP		0.84

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr7-66460341;