20-35433389-A-G

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 2P and 8B. PM2 BP4_Moderate BP6_Moderate BS1

The NM_000557.5(GDF5):c.*520T>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00123 in 311,402 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.0022 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00031 (0 hom.)
• Consequence: GDF5 NM_000557.5 3_prime_UTR
• Clinical Significance: Benign/Likely benign criteria provided, single submitter B:5
• Conservation: PhyloP100: -0.0320

Genes affected

GDF5 (HGNC:4220): (growth differentiation factor 5) This gene encodes a secreted ligand of the TGF-beta (transforming growth factor-beta) superfamily of proteins. Ligands of this family bind various TGF-beta receptors leading to recruitment and activation of SMAD family transcription factors that regulate gene expression. The encoded preproprotein is proteolytically processed to generate each subunit of the disulfide-linked homodimer. This protein regulates the development of numerous tissue and cell types, including cartilage, joints, brown fat, teeth, and the growth of neuronal axons and dendrites. Mutations in this gene are associated with acromesomelic dysplasia, brachydactyly, chondrodysplasia, multiple synostoses syndrome, proximal symphalangism, and susceptibility to osteoarthritis. [provided by RefSeq, Aug 2016]

GDF5-AS1 (HGNC:33435): (GDF5 antisense RNA 1) Predicted to be located in mitochondrion. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.46).
• BP6: Variant 20-35433389-A-G is Benign according to our data. Variant chr20-35433389-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 338309.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00218 (332/152272) while in subpopulation AFR AF= 0.00758 (315/41546). AF 95% confidence interval is 0.00689. There are 0 homozygotes in gnomad4. There are 165 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GDF5	NM_000557.5	c.*520T>C		3_prime_UTR_variant	2/2	ENST00000374369.8
GDF5-AS1	NR_161326.1	n.135+226A>G		intron_variant, non_coding_transcript_variant
GDF5	NM_001319138.2	c.*520T>C		3_prime_UTR_variant	4/4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GDF5	ENST00000374369.8	c.*520T>C		3_prime_UTR_variant	2/2	1	NM_000557.5	P1
GDF5	ENST00000374372.1	c.*520T>C		3_prime_UTR_variant	4/4	1		P1
GDF5-AS1	ENST00000374375.1	n.135+226A>G		intron_variant, non_coding_transcript_variant		2

Frequencies

GnomAD3 genomes AF: 0.00218 AC: 332 AN: 152154 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00760

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00105

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: 0.000478

GnomAD4 exome AF: 0.000314 AC: 50 AN: 159130 Hom.: 0 Cov.: 0 AF XY: 0.000208 AC XY: 18 AN XY: 86600

Gnomad4 AFR exome AF: 0.00872

Gnomad4 AMR exome AF: 0.000766

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000112

Gnomad4 OTH exome AF: 0.000633

GnomAD4 genome AF: 0.00218 AC: 332 AN: 152272 Hom.: 0 Cov.: 32 AF XY: 0.00222 AC XY: 165 AN XY: 74448

Gnomad4 AFR AF: 0.00758

Gnomad4 AMR AF: 0.00105

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.000473

Alfa AF: 0.000840 Hom.: 0

Bravo AF: 0.00235

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:5

Revision: criteria provided, single submitter

Submissions by phenotype

Grebe syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Multiple synostoses syndrome 2 Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Brachydactyly Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Acromesomelic dysplasia 2B Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Acromesomelic dysplasia 2C, Hunter-Thompson type Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.46
Cadd	Benign	8.5
Dann	Benign	0.64

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: rs188252641; hg19: chr20-34021187;