chr7-100101764-ACAAAGACTGTATC-A

Position:

• chr7-100101764-ACAAAGACTGTATC-A

Variant summary

Our verdict is Pathogenic. Variant got 13 ACMG points: 13P and 0B. PVS1 PM2 PP3 PP5_Moderate

The NM_004722.4(AP4M1):​c.52_58+6del variant causes a splice donor, splice donor 5th base, coding sequence, 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 splice_donor, splice_donor_5th_base, coding_sequence, 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 Pathogenic. Variant got 13 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: No computational evidence supports a deleterious effect, but strongly conserved according to phyloP
• 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/exons	MANE	UniProt
AP4M1	NM_004722.4	c.52_58+6del		splice_donor_variant, splice_donor_5th_base_variant, coding_sequence_variant, intron_variant	1/15	ENST00000359593.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AP4M1	ENST00000359593.9	c.52_58+6del		splice_donor_variant, splice_donor_5th_base_variant, coding_sequence_variant, intron_variant	1/15	1	NM_004722.4	P3

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

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 13, 2022

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 1497146). 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. 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). -

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;