21-46235370-G-T

Variant names:

• chr21-46235370-G-T
• rs775558146
• NM_003906.5:c.5841C>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_003906.5(MCM3AP):​c.5841C>A​(p.Gly1947Gly) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,834 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. G1947G) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MCM3AP NM_003906.5 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -5.18
• Publications: 0 publications found

Genes affected

MCM3AP (HGNC:6946): (minichromosome maintenance complex component 3 associated protein) The minichromosome maintenance protein 3 (MCM3) is one of the MCM proteins essential for the initiation of DNA replication. The protein encoded by this gene is a MCM3 binding protein. It was reported to have phosphorylation-dependent DNA-primase activity, which was up-regulated in antigen immunization induced germinal center. This protein was demonstrated to be an acetyltransferase that acetylates MCM3 and plays a role in DNA replication. The mutagenesis of a nuclear localization signal of MCM3 affects the binding of this protein with MCM3, suggesting that this protein may also facilitate MCM3 nuclear localization. This gene is expressed in the brain or in neuronal tissue. An allelic variant encoding amino acid Lys at 915, instead of conserved Glu, has been identified in patients with mild intellectual disability. [provided by RefSeq, Jan 2014]

MCM3AP-AS1 (HGNC:16417): (MCM3AP antisense RNA 1)

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.97).
• BP7: Synonymous conserved (PhyloP=-5.18 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003906.5. 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
	MCM3AP	NM_003906.5	MANE Select	c.5841C>A	p.Gly1947Gly	synonymous	Exon 28 of 28	NP_003897.2
	MCM3AP-AS1	NR_002776.4		n.37-5464G>T		intron	N/A
	MCM3AP-AS1	NR_110565.1		n.237+4843G>T		intron	N/A

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MCM3AP	ENST00000291688.6	TSL:1 MANE Select	c.5841C>A	p.Gly1947Gly	synonymous	Exon 28 of 28	ENSP00000291688.1	O60318-1
	MCM3AP-AS1	ENST00000420074.1	TSL:1	n.1864G>T		non_coding_transcript_exon	Exon 2 of 2
	MCM3AP	ENST00000467026.5	TSL:1	n.2434C>A		non_coding_transcript_exon	Exon 13 of 13

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251390 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 1461834 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727224

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

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.0000224 AC: 1 AN: 44724

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111968

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ 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 Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.97
CADD	Benign	0.023
DANN	Benign	0.74
PhyloP100		-5.2

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: rs775558146; hg19: chr21-47655284;