10-123009030-A-T

Position:

• chr10-123009030-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_001330174.3(ACADSB):​c.-205A>T variant causes a 5 prime UTR premature start codon gain change. The variant allele was found at a frequency of 0.00000194 in 1,547,764 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: ACADSB NM_001330174.3 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.63

Genes affected

ACADSB (HGNC:91): (acyl-CoA dehydrogenase short/branched chain) Short/branched chain acyl-CoA dehydrogenase(ACADSB) is a member of the acyl-CoA dehydrogenase family of enzymes that catalyze the dehydrogenation of acyl-CoA derivatives in the metabolism of fatty acids or branch chained amino acids. Substrate specificity is the primary characteristic used to define members of this gene family. The ACADSB gene product has the greatest activity towards the short branched chain acyl-CoA derivative, (S)-2-methylbutyryl-CoA, but also reacts significantly with other 2-methyl branched chain substrates and with short straight chain acyl-CoAs. The cDNA encodes for a mitochondrial precursor protein which is cleaved upon mitochondrial import and predicted to yield a mature peptide of approximately 43.7-KDa. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ACADSB	NM_001609.4	c.1A>T	p.Met1?	initiator_codon_variant	1/11	ENST00000358776.7	NP_001600.1
ACADSB	NM_001330174.3	c.-205A>T		5_prime_UTR_premature_start_codon_gain_variant	1/10		NP_001317103.1
ACADSB	NM_001330174.3	c.-205A>T		5_prime_UTR_variant	1/10		NP_001317103.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ACADSB	ENST00000358776.7	c.1A>T	p.Met1?	initiator_codon_variant	1/11	1	NM_001609.4	ENSP00000357873.3
ACADSB	ENST00000368869	c.-201A>T		5_prime_UTR_premature_start_codon_gain_variant	1/10	2		ENSP00000357862.4
ACADSB	ENST00000368869	c.-201A>T		5_prime_UTR_variant	1/10	2		ENSP00000357862.4

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152094 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000143 AC: 2 AN: 1395670 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 688554

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 0.00000185

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152094 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74302

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Aug 02, 2023

Variant summary: ACADSB c.1A>T (p.Met1Leu) alters the initiation codon and is predicted to result either in absence of the protein or truncation of the encoded protein due to translation initiation at a downstream codon. The next in-frame initiation codon occurs at Met62 in exon 2. Two of three in-silico tools predict a benign effect of the variant on protein function. The variant was absent in 148616 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.1A>T in individuals affected with Deficiency of 2-methylbutyryl-CoA Dehydrogenase and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.37
CADD	Benign	21
DANN	Benign	0.63
DEOGEN2	Benign	0.10	T
Eigen	Benign	-0.77
Eigen_PC	Benign	-0.78
FATHMM_MKL	Benign	0.10	N
LIST_S2	Uncertain	0.90	D
M_CAP	Pathogenic	0.97	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	0.23	D
PROVEAN	Benign	-0.28	N
REVEL	Uncertain	0.52
Sift	Pathogenic	0.0	D
Sift4G	Benign	0.16	T
Polyphen		0.0	B
Vest4		0.87
MutPred		0.94		Loss of catalytic residue at M1 (P = 0.0487);
MVP		0.75
ClinPred		0.99	D
GERP RS		1.4
Varity_R		0.94
gMVP		0.45

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

Publications

LitVar

Other links and lift over

dbSNP: rs1849951239; hg19: chr10-124768546;