NM_003172.4:c.900G>T

Variant names:

• chr9-133351916-C-A
• rs781873188
• NM_003172.4:c.900G>T

Variant summary

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

The NM_003172.4(SURF1):​c.900G>T​(p.Val300Val) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,258 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. V300V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SURF1 NM_003172.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.291
• Publications: 0 publications found

Genes affected

SURF1 (HGNC:11474): (SURF1 cytochrome c oxidase assembly factor) This gene encodes a protein localized to the inner mitochondrial membrane and thought to be involved in the biogenesis of the cytochrome c oxidase complex. The protein is a member of the SURF1 family, which includes the related yeast protein SHY1 and rickettsial protein RP733. The gene is located in the surfeit gene cluster, a group of very tightly linked genes that do not share sequence similarity, where it shares a bidirectional promoter with SURF2 on the opposite strand. Defects in this gene are a cause of Leigh syndrome, a severe neurological disorder that is commonly associated with systemic cytochrome c oxidase deficiency. [provided by RefSeq, Jul 2008]

SURF1 Gene-Disease associations (from GenCC):

• Leigh syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen
• mitochondrial complex IV deficiency, nuclear type 1

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
• mitochondrial disease

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• Charcot-Marie-Tooth disease type 4K

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)
• Leigh syndrome with cardiomyopathy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Leigh syndrome with leukodystrophy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: 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=-0.67).
• BP7: Synonymous conserved (PhyloP=-0.291 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003172.4. 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
	SURF1	NM_003172.4	MANE Select	c.900G>T	p.Val300Val	synonymous	Exon 9 of 9	NP_003163.1	Q15526-1
	SURF1	NM_001280787.1		c.573G>T	p.Val191Val	synonymous	Exon 8 of 8	NP_001267716.1	A0A087WYS9

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SURF1	ENST00000371974.8	TSL:1 MANE Select	c.900G>T	p.Val300Val	synonymous	Exon 9 of 9	ENSP00000361042.3	Q15526-1
	SURF1	ENST00000615505.4	TSL:1	c.573G>T	p.Val191Val	synonymous	Exon 8 of 8	ENSP00000482067.1	A0A087WYS9
	SURF1	ENST00000886676.1		c.870G>T	p.Val290Val	synonymous	Exon 9 of 9	ENSP00000556735.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000400 AC: 1 AN: 250044 AF XY: 0.00000739

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: 6.84e-7 AC: 1 AN: 1461258 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726860

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

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44638

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26100

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86086

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53292

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111822

Other (OTH) AF: 0.0000166 AC: 1 AN: 60384

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.67
CADD	Benign	0.18
DANN	Benign	0.71
PhyloP100		-0.29

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs781873188; hg19: chr9-136218771;