10-95606919-G-T

Variant names:

• chr10-95606919-G-T
• rs762271422
• NM_002860.4:c.2231C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_002860.4(ALDH18A1):​c.2231C>A​(p.Ser744*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,834 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. S744S) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ALDH18A1 NM_002860.4 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.46
• Publications: 0 publications found

Genes affected

ALDH18A1 (HGNC:9722): (aldehyde dehydrogenase 18 family member A1) This gene is a member of the aldehyde dehydrogenase family and encodes a bifunctional ATP- and NADPH-dependent mitochondrial enzyme with both gamma-glutamyl kinase and gamma-glutamyl phosphate reductase activities. The encoded protein catalyzes the reduction of glutamate to delta1-pyrroline-5-carboxylate, a critical step in the de novo biosynthesis of proline, ornithine and arginine. Mutations in this gene lead to hyperammonemia, hypoornithinemia, hypocitrullinemia, hypoargininemia and hypoprolinemia and may be associated with neurodegeneration, cataracts and connective tissue diseases. Alternatively spliced transcript variants, encoding different isoforms, have been described for this gene. [provided by RefSeq, Jul 2008]

ALDH18A1 Gene-Disease associations (from GenCC):

• cutis laxa, autosomal dominant 3

  Inheritance: AD, SD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• ALDH18A1-related de Barsy syndrome

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, G2P, Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics
• autosomal recessive complex spastic paraplegia type 9B

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, SUPPORTIVE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics
• P5CS deficiency

  Inheritance: SD Classification: DEFINITIVE Submitted by: ClinGen, Illumina
• hereditary spastic paraplegia 9A

  Inheritance: AD, SD Classification: MODERATE, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics
• autosomal dominant complex spastic paraplegia type 9B

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal dominant cutis laxa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 7 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002860.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALDH18A1	NM_002860.4	MANE Select	c.2231C>A	p.Ser744*	stop_gained	Exon 18 of 18	NP_002851.2
	ALDH18A1	NM_001323413.2		c.2231C>A	p.Ser744*	stop_gained	Exon 18 of 18	NP_001310342.1
	ALDH18A1	NM_001323414.2		c.2231C>A	p.Ser744*	stop_gained	Exon 18 of 18	NP_001310343.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALDH18A1	ENST00000371224.7	TSL:1 MANE Select	c.2231C>A	p.Ser744*	stop_gained	Exon 18 of 18	ENSP00000360268.2
	ALDH18A1	ENST00000371221.3	TSL:1	c.2225C>A	p.Ser742*	stop_gained	Exon 18 of 18	ENSP00000360265.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461834 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727230

⚠️ 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: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5756

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111986

Other (OTH) AF: 0.00 AC: 0 AN: 60390

⚠️ 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.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.63
CADD	Pathogenic	43
DANN	Uncertain	0.99
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		9.5
Vest4		0.10
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=2/198	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs762271422; hg19: chr10-97366676;