rs1555938722

Variant names:

• chr22-30937940-T-TCAACAACCC
• rs1555938722
• NM_001303256.3:c.1235_1243dupGGGTTGTTG

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PM4

The NM_001303256.3(MORC2):​c.1235_1243dupGGGTTGTTG​(p.Gly412_Val414dup) variant causes a conservative inframe insertion change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: MORC2 NM_001303256.3 conservative_inframe_insertion
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.84
• Publications: 0 publications found

Genes affected

MORC2 (HGNC:23573): (MORC family CW-type zinc finger 2) This gene encodes a member of the Microrchidia (MORC) protein superfamily. The encoded protein is known to regulate the condensation of heterochromatin in response to DNA damage and play a role in repressing transcription. The protein has been found to regulate the activity of ATP citrate lyase via specific interaction with this enzyme in the cytosol of lipogenic breast cancer cells. The protein also plays a role in lipogenesis and adipocyte differentiation. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Feb 2016]

MORC2 Gene-Disease associations (from GenCC):

• Charcot-Marie-Tooth disease axonal type 2Z

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet, Labcorp Genetics (formerly Invitae)
• developmental delay, impaired growth, dysmorphic facies, and axonal neuropathy

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• Leigh syndrome

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

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

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_001303256.3
• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_001303256.3.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MORC2	NM_001303256.3	c.1235_1243dupGGGTTGTTG	p.Gly412_Val414dup	conservative_inframe_insertion	Exon 14 of 26	ENST00000397641.8	NP_001290185.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MORC2	ENST00000397641.8	c.1235_1243dupGGGTTGTTG	p.Gly412_Val414dup	conservative_inframe_insertion	Exon 14 of 26	5	NM_001303256.3	ENSP00000380763.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Charcot-Marie-Tooth disease axonal type 2Z Uncertain:1

Jul 05, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant, c.1049_1057dup, results in the insertion of 3 amino acid(s) of the MORC2 protein (p.Gly350_Val352dup), but otherwise preserves the integrity of the reading frame. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MORC2-related conditions. ClinVar contains an entry for this variant (Variation ID: 475572). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		5.8

Splicing

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

Other links and lift over

dbSNP: rs1555938722; hg19: chr22-31333927;