NM_024596.5:c.22+1G>A

Variant names:

• chr8-6406690-G-A
• rs1187479362
• NM_024596.5:c.22+1G>A

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_024596.5(MCPH1):​c.22+1G>A variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MCPH1 NM_024596.5 splice_donor, intron
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.460
• Publications: 0 publications found

Genes affected

MCPH1 (HGNC:6954): (microcephalin 1) This gene encodes a DNA damage response protein. The encoded protein may play a role in G2/M checkpoint arrest via maintenance of inhibitory phosphorylation of cyclin-dependent kinase 1. Mutations in this gene have been associated with primary autosomal recessive microcephaly 1 and premature chromosome condensation syndrome. Alternatively spliced transcript variants have been described. [provided by RefSeq, Feb 2010]

MCPH1-DT (HGNC:55599): (MCPH1 divergent transcript)

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.025119618 fraction of the gene. Cryptic splice site detected, with MaxEntScore 7.8, offset of 5, new splice context is: gagGTactt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_024596.5. 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
	MCPH1	NM_024596.5	MANE Select	c.22+1G>A		splice_donor intron	N/A	NP_078872.3	Q8NEM0-1
	MCPH1	NM_001322042.2		c.22+1G>A		splice_donor intron	N/A	NP_001308971.2	A0A8I5KV10
	MCPH1	NM_001410917.1		c.22+1G>A		splice_donor intron	N/A	NP_001397846.1	A0A8I5KPV6

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MCPH1	ENST00000344683.10	TSL:1 MANE Select	c.22+1G>A		splice_donor intron	N/A	ENSP00000342924.5	Q8NEM0-1
	MCPH1	ENST00000519480.6	TSL:1	c.22+1G>A		splice_donor intron	N/A	ENSP00000430962.1	Q8NEM0-3
	MCPH1	ENST00000692836.1		c.22+1G>A		splice_donor intron	N/A	ENSP00000509971.1	A0A8I5KX36

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Benign	-0.14
CADD	Pathogenic	33
DANN	Benign	0.94
Eigen	Uncertain	0.51
Eigen_PC	Benign	0.18
FATHMM_MKL	Benign	0.16	N
PhyloP100		0.46
GERP RS		1.2
PromoterAI		-0.40	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.1
Mutation Taster		=63/37	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.82		Position offset: 4
DS_DL_spliceai		1.0		Position offset: -1

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

Other links and lift over

dbSNP: rs1187479362; hg19: chr8-6264211;