chr17-82752214-G-C

Variant names:

• chr17-82752214-G-C
• rs768875605
• NM_005993.5:c.21G>C

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_005993.5(TBCD):​c.21G>C​(p.Pro7Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000788 in 1,522,398 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. P7P) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000080 (0 hom.)
• Consequence: TBCD NM_005993.5 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.106
• Publications: 0 publications found

Genes affected

TBCD (HGNC:11581): (tubulin folding cofactor D) Cofactor D is one of four proteins (cofactors A, D, E, and C) involved in the pathway leading to correctly folded beta-tubulin from folding intermediates. Cofactors A and D are believed to play a role in capturing and stabilizing beta-tubulin intermediates in a quasi-native confirmation. Cofactor E binds to the cofactor D/beta-tubulin complex; interaction with cofactor C then causes the release of beta-tubulin polypeptides that are committed to the native state. [provided by RefSeq, Jul 2008]

TBCD Gene-Disease associations (from GenCC):

• early-onset progressive diffuse brain atrophy-microcephaly-muscle weakness-optic atrophy syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, G2P, Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.59).
• BP7: Synonymous conserved (PhyloP=0.106 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005993.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TBCD	NM_005993.5	MANE Select	c.21G>C	p.Pro7Pro	synonymous	Exon 1 of 39	NP_005984.3
	TBCD	NM_001411101.1		c.21G>C	p.Pro7Pro	synonymous	Exon 1 of 38	NP_001398030.1	A0A804HLI2
	TBCD	NM_001411102.1		c.21G>C	p.Pro7Pro	synonymous	Exon 1 of 38	NP_001398031.1	A0A804HJ32

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TBCD	ENST00000355528.9	TSL:1 MANE Select	c.21G>C	p.Pro7Pro	synonymous	Exon 1 of 39	ENSP00000347719.4	Q9BTW9-1
	TBCD	ENST00000684760.1		c.21G>C	p.Pro7Pro	synonymous	Exon 1 of 40	ENSP00000507696.1	A0A804HJY5
	TBCD	ENST00000684349.1		c.21G>C	p.Pro7Pro	synonymous	Exon 1 of 39	ENSP00000508067.1	A0A804HKT8

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152142 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000355 AC: 4 AN: 112752 AF XY: 0.0000480

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000803 AC: 11 AN: 1370256 Hom.: 0 Cov.: 30 AF XY: 0.0000133 AC XY: 9 AN XY: 676040

African (AFR) AF: 0.00 AC: 0 AN: 28104

American (AMR) AF: 0.00 AC: 0 AN: 33558

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 24306

East Asian (EAS) AF: 0.00 AC: 0 AN: 32008

South Asian (SAS) AF: 0.000142 AC: 11 AN: 77262

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 43878

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4514

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1069756

Other (OTH) AF: 0.00 AC: 0 AN: 56870

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152142 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74322

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000241 AC: 1 AN: 41454

American (AMR) AF: 0.00 AC: 0 AN: 15282

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5188

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10600

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 67996

Other (OTH) AF: 0.00 AC: 0 AN: 2092

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

Asia WGS AF: 0.000289 AC: 1 AN: 3474

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.59
CADD	Benign	8.6
DANN	Benign	0.57
PhyloP100		0.11
PromoterAI		-0.064	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8

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: rs768875605; hg19: chr17-80710090;