rs869320753

Variant names:

• chr20-5977950-T-TTA
• rs869320753
• NM_032485.6:c.1470_1471insTA

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_032485.6(MCM8):​c.1470_1471insTA​(p.Leu491TyrfsTer88) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 33)
• Consequence: MCM8 NM_032485.6 frameshift
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 2.85
• Publications: 0 publications found

Genes affected

MCM8 (HGNC:16147): (minichromosome maintenance 8 homologous recombination repair factor) 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 mini-chromosome maintenance proteins is a key component of the pre-replication complex and may be involved in the formation of replication forks and in the recruitment of other DNA replication related proteins. This protein contains the central domain that is conserved among the mini-chromosome maintenance proteins. The encoded protein may interact with other mini-chromosome maintenance proteins and play a role in DNA replication. This gene may be associated with length of reproductive lifespan and menopause. Alternatively spliced transcript variants encoding distinct isoforms have been described. [provided by RefSeq, Jul 2013]

MCM8 Gene-Disease associations (from GenCC):

• premature ovarian failure 10

  Inheritance: AR, AD Classification: STRONG, MODERATE, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• colorectal cancer

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ENSG00000286235 (HGNC:):

ACMG classification

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 20-5977950-T-TTA is Pathogenic according to our data. Variant chr20-5977950-T-TTA is described in ClinVar as Pathogenic. ClinVar VariationId is 208811.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_032485.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MCM8	NM_032485.6	MANE Select	c.1470_1471insTA	p.Leu491TyrfsTer88	frameshift	Exon 13 of 19	NP_115874.3
	MCM8	NM_001281521.2		c.1590_1591insTA	p.Leu531TyrfsTer88	frameshift	Exon 13 of 19	NP_001268450.1	Q9UJA3-4
	MCM8	NM_001281520.2		c.1470_1471insTA	p.Leu491TyrfsTer88	frameshift	Exon 13 of 19	NP_001268449.1	Q9UJA3-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MCM8	ENST00000610722.4	TSL:1 MANE Select	c.1470_1471insTA	p.Leu491TyrfsTer88	frameshift	Exon 13 of 19	ENSP00000478141.1	Q9UJA3-1
	ENSG00000286235	ENST00000652720.1		c.1470_1471insTA	p.Leu491TyrfsTer88	frameshift	Exon 13 of 24	ENSP00000498784.1	A0A494C100
	MCM8	ENST00000378886.6	TSL:1	c.1590_1591insTA	p.Leu531TyrfsTer88	frameshift	Exon 13 of 19	ENSP00000368164.2	Q9UJA3-4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Premature ovarian failure 10 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.8
Mutation Taster		=1/199	disease causing (ClinVar)

Splicing

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

Other links and lift over

dbSNP: rs869320753; hg19: chr20-5958596;