7-100101764-ACAAAGACTGTATC-A

Variant names:

• chr7-100101764-ACAAAGACTGTATC-A
• rs1350685858
• ENST00000343023.10:c.-483_-471delGATACAGTCTTTG

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_004722.4(AP4M1):​c.52_58+6delAAAGACTGTATCC​(p.Lys18fs) variant causes a frameshift, splice donor, splice region, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000662 in 151,076 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: AP4M1 NM_004722.4 frameshift, splice_donor, splice_region, intron
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 8.27

Genes affected

MCM7 (HGNC:6950): (minichromosome maintenance complex component 7) The protein encoded by this gene is one of the highly conserved mini-chromosome maintenance proteins (MCM) that are essential for the initiation of eukaryotic genome replication. The hexameric protein complex formed by the MCM proteins is a key component of the pre-replication complex (pre_RC) and may be involved in the formation of replication forks and in the recruitment of other DNA replication related proteins. The MCM complex consisting of this protein and MCM2, 4 and 6 proteins possesses DNA helicase activity, and may act as a DNA unwinding enzyme. Cyclin D1-dependent kinase, CDK4, is found to associate with this protein, and may regulate the binding of this protein with the tumorsuppressor protein RB1/RB. Alternatively spliced transcript variants encoding distinct isoforms have been reported. [provided by RefSeq, Jul 2008]

AP4M1 (HGNC:574): (adaptor related protein complex 4 subunit mu 1) This gene encodes a subunit of the heterotetrameric AP-4 complex. The encoded protein belongs to the adaptor complexes medium subunits family. This AP-4 complex is involved in the recognition and sorting of cargo proteins with tyrosine-based motifs from the trans-golgi network to the endosomal-lysosomal system. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 11 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-100101764-ACAAAGACTGTATC-A is Pathogenic according to our data. Variant chr7-100101764-ACAAAGACTGTATC-A is described in ClinVar as [Pathogenic]. Clinvar id is 1497146.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
AP4M1	NM_004722.4	c.52_58+6delAAAGACTGTATCC	p.Lys18fs	frameshift_variant, splice_donor_variant, splice_region_variant, intron_variant	Exon 1 of 15	ENST00000359593.9	NP_004713.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
AP4M1	ENST00000359593.9	c.52_58+6delAAAGACTGTATCC	p.Lys18fs	frameshift_variant, splice_donor_variant, splice_region_variant, intron_variant	Exon 1 of 15	1	NM_004722.4	ENSP00000352603.4

Frequencies

GnomAD3 genomes AF: 0.00000662 AC: 1 AN: 151076 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000657

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: 0.00

Gnomad OTH AF: 0.00

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.00000662 AC: 1 AN: 151076 Hom.: 0 Cov.: 33 AF XY: 0.0000136 AC XY: 1 AN XY: 73754

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000657

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000113

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary spastic paraplegia 50 Pathogenic:1

Sep 13, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (gnomAD no frequency). This variant results in the deletion of part of exon 1 (c.52_58+6del) of the AP4M1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in AP4M1 are known to be pathogenic (PMID: 24700674, 25496299, 25558065). This variant has been observed in individual(s) with clinical features of AP4M1-related conditions (Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 1497146). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1350685858; hg19: chr7-99699387;