NM_005589.4:c.1156C>T

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1PM2PP5

The NM_005589.4(ALDH6A1):​c.1156C>T​(p.Arg386*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000217 in 1,613,668 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 Conflicting classifications of pathogenicity (no stars). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

ALDH6A1
NM_005589.4 stop_gained

Scores

2
4
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:2

Conservation

PhyloP100: 2.73

Publications

1 publications found
Variant links:
Genes affected
ALDH6A1 (HGNC:7179): (aldehyde dehydrogenase 6 family member A1) This gene encodes a member of the aldehyde dehydrogenase protein family. The encoded protein is a mitochondrial methylmalonate semialdehyde dehydrogenase that plays a role in the valine and pyrimidine catabolic pathways. This protein catalyzes the irreversible oxidative decarboxylation of malonate and methylmalonate semialdehydes to acetyl- and propionyl-CoA. Methylmalonate semialdehyde dehydrogenase deficiency is characterized by elevated beta-alanine, 3-hydroxypropionic acid, and both isomers of 3-amino and 3-hydroxyisobutyric acids in urine organic acids. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Jun 2013]
BBOF1 (HGNC:19855): (basal body orientation factor 1) Predicted to be involved in motile cilium assembly. Predicted to be located in ciliary basal body. [provided by Alliance of Genome Resources, Apr 2022]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 11 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 14-74066773-G-A is Pathogenic according to our data. Variant chr14-74066773-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 522934.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ALDH6A1NM_005589.4 linkc.1156C>T p.Arg386* stop_gained Exon 9 of 12 ENST00000553458.6 NP_005580.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ALDH6A1ENST00000553458.6 linkc.1156C>T p.Arg386* stop_gained Exon 9 of 12 1 NM_005589.4 ENSP00000450436.1

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
151714
Hom.:
0
Cov.:
32
show subpopulations
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000517
AC:
13
AN:
251344
AF XY:
0.0000515
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000704
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000226
AC:
33
AN:
1461836
Hom.:
0
Cov.:
32
AF XY:
0.0000234
AC XY:
17
AN XY:
727218
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000225
AC:
25
AN:
1111964
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.457
Heterozygous variant carriers
0
2
4
7
9
11
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
151832
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74190
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41378
American (AMR)
AF:
0.00
AC:
0
AN:
15204
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4808
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10502
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
67986
Other (OTH)
AF:
0.00
AC:
0
AN:
2106
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000165
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.0000741
AC:
9

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Inborn genetic diseases Pathogenic:1
Jan 27, 2021
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1156C>T (p.R386*) alteration, located in exon 9 (coding exon 9) of the ALDH6A1 gene, consists of a C to T substitution at nucleotide position 1156. This changes the amino acid from an arginine (R) to a stop codon at amino acid position 386. This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. Based on data from the Genome Aggregation Database (gnomAD) database, the ALDH6A1 c.1156C>T alteration was observed in 0.01% (13/251344) of total alleles studied. Based on the available evidence, this alteration is classified as pathogenic. -

Methylmalonate semialdehyde dehydrogenase deficiency Pathogenic:1
May 03, 2020
Genomic Research Center, Shahid Beheshti University of Medical Sciences
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Jun 26, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: ALDH6A1 c.1156C>T (p.Arg386X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, however current evidence is not sufficient to establish loss of function as a mechanism for disease. The variant allele was found at a frequency of 5.2e-05 in 251344 control chromosomes (gnomAD). This frequency is not significantly higher than estimated for a pathogenic variant in ALDH6A1 causing Methylmalonate Semialdehyde Dehydrogenase Deficiency, allowing no conclusion about variant significance. To our knowledge, no occurrence of c.1156C>T in individuals affected with Methylmalonate Semialdehyde Dehydrogenase Deficiency and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 522934). Based on the evidence outlined above, the variant was classified as uncertain significance. -

not provided Uncertain:1
Oct 10, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Arg386*) in the ALDH6A1 gene. It is expected to result in an absent or disrupted protein product. However, the current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in ALDH6A1 cause disease. This variant is present in population databases (rs781767219, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with ALDH6A1-related conditions. ClinVar contains an entry for this variant (Variation ID: 522934). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.41
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
38
DANN
Uncertain
0.99
Eigen
Uncertain
0.42
Eigen_PC
Uncertain
0.27
FATHMM_MKL
Uncertain
0.92
D
PhyloP100
2.7
Vest4
0.55
GERP RS
2.4
Mutation Taster
=1/199
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs781767219; hg19: chr14-74533476; COSMIC: COSV63247342; COSMIC: COSV63247342; API