NM_024596.5:c.80C>T

Variant names:

• chr8-6409336-C-T
• rs199422124
• NM_024596.5:c.80C>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_024596.5(MCPH1):​c.80C>T​(p.Thr27Ile) variant causes a missense change. The variant allele was found at a frequency of 0.00000124 in 1,613,876 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T27R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MCPH1 NM_024596.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.83
• Publications: 12 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 Gene-Disease associations (from GenCC):

• microcephaly 1, primary, autosomal recessive

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• microcephaly with intellectual disability

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• autosomal recessive primary microcephaly

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• hereditary breast carcinoma

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• familial ovarian cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• 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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MCPH1	NM_024596.5	MANE Select	c.80C>T	p.Thr27Ile	missense	Exon 2 of 14	NP_078872.3
	MCPH1	NM_001322042.2		c.80C>T	p.Thr27Ile	missense	Exon 2 of 15	NP_001308971.2
	MCPH1	NM_001410917.1		c.80C>T	p.Thr27Ile	missense	Exon 2 of 14	NP_001397846.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MCPH1	ENST00000344683.10	TSL:1 MANE Select	c.80C>T	p.Thr27Ile	missense	Exon 2 of 14	ENSP00000342924.5
	MCPH1	ENST00000519480.6	TSL:1	c.80C>T	p.Thr27Ile	missense	Exon 2 of 8	ENSP00000430962.1
	MCPH1	ENST00000692836.1		c.80C>T	p.Thr27Ile	missense	Exon 2 of 13	ENSP00000509971.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152138 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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

GnomAD2 exomes AF: 0.00000401 AC: 1 AN: 249564 AF XY: 0.00

Gnomad AFR exome AF: 0.0000646

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461738 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727184

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000299 AC: 1 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111894

Other (OTH) AF: 0.00 AC: 0 AN: 60390

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152138 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74306

African (AFR) AF: 0.0000241 AC: 1 AN: 41440

American (AMR) AF: 0.00 AC: 0 AN: 15282

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10576

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68026

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.33
BayesDel_addAF	Benign	-0.039	T
BayesDel_noAF	Benign	-0.11
CADD	Pathogenic	26
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.43	T
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Benign	0.076	D
MetaRNN	Uncertain	0.59	D
MetaSVM	Uncertain	0.22	D
MutationAssessor	Benign	1.1	L
PhyloP100		6.8
PrimateAI	Uncertain	0.55	T
PROVEAN	Uncertain	-2.9	D
REVEL	Uncertain	0.54
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.059	T
Polyphen		1.0	D
Vest4		0.59
MutPred		0.53		Loss of disorder (P = 0.0306)
MVP		0.87
ClinPred		0.89	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.51
gMVP		0.33
Mutation Taster		=22/78	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs199422124; hg19: chr8-6266857;