chr2-99162273-G-A

Position:

• chr2-99162273-G-A

Variant summary

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

The NM_145199.3(LIPT1):​c.316G>A​(p.Val106Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,422 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: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: LIPT1 NM_145199.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.78

Genes affected

LIPT1 (HGNC:29569): (lipoyltransferase 1) The process of transferring lipoic acid to proteins is a two-step process. The first step is the activation of lipoic acid by lipoate-activating enzyme to form lipoyl-AMP. For the second step, the protein encoded by this gene transfers the lipoyl moiety to apoproteins. Alternative splicing results in multiple transcript variants. A related pseudogene has been identified on chromosome 13. Read-through transcription also exists between this gene and the neighboring downstream mitochondrial ribosomal protein L30 (MRPL30) gene. [provided by RefSeq, Mar 2011]

MITD1 (HGNC:25207): (microtubule interacting and trafficking domain containing 1) Abscission, the separation of daughter cells at the end of cytokinesis, is effected by endosomal sorting complexes required for transport III (ESCRT-III). The protein encoded by this gene functions as a homodimer, with the N-termini binding to a subset of ESCRT-III subunits and the C-termini binding to membranes. The encoded protein regulates ESCRT-III activity and is required for proper cytokinesis. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2016]

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, 0.947

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LIPT1	NM_145199.3	c.316G>A	p.Val106Ile	missense_variant	2/2	ENST00000651691.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LIPT1	ENST00000651691.1	c.316G>A	p.Val106Ile	missense_variant	2/2		NM_145199.3	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460422 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726598

Gnomad4 AFR exome AF: 0.0000299

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

See cases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Pediatric Department, Xiangya Hospital, Central South University

-

This variant was observed in compound heterozygosity with variant (c.302G>A) -

Lipoyl transferase 1 deficiency Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Neuberg Centre For Genomic Medicine, NCGM

-

The missense variant c.316G>A (p.Val106Ile) in LIPT1 gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. This variant has not been reported to the ClinVar database.The p.Val106Ile variant is novel (not in any individuals) in gnomAD Exomes and 1000 Genomes. The amino acid Val at position 106 is changed to a Ile changing protein sequence and it might alter its composition and physico-chemical properties. The variant is predicted to be damaging by both SIFT and PolyPhen2. The residue is conserved across species. The amino acid change p.Val106Ile in LIPT1 is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Pathogenic	0.28	D
BayesDel_noAF	Pathogenic	0.17
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Benign	0.21	T;T;.;T;.
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.88	D;.;D;D;D
M_CAP	Uncertain	0.18	D
MetaRNN	Pathogenic	0.91	D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.7	M;M;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Uncertain	0.53	T
PROVEAN	Benign	-0.98	N;N;N;N;N
REVEL	Pathogenic	0.74
Sift	Pathogenic	0.0	D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D
Polyphen		1.0	D;D;.;.;.
Vest4		0.74
MutPred		0.83		Loss of glycosylation at S101 (P = 0.1275);Loss of glycosylation at S101 (P = 0.1275);Loss of glycosylation at S101 (P = 0.1275);Loss of glycosylation at S101 (P = 0.1275);Loss of glycosylation at S101 (P = 0.1275);
MVP		0.88
ClinPred		0.99	D
GERP RS		4.9
Varity_R		0.38
gMVP		0.62

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: rs1368952585; hg19: chr2-99778736;