12-8932728-CGCAGCAGCA-CGCAGCAGCAGCA

Variant names:

• chr12-8932728-C-CGCA
• rs368945524
• NM_004426.3:c.1287_1289dupGCA

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PM4_Supporting

The NM_004426.3(PHC1):​c.1287_1289dupGCA​(p.Gln430dup) variant causes a disruptive inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000678 in 151,974 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.00068 (0 hom., cov: 27)
  • Exomes 𝑓: 0.00011 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PHC1 NM_004426.3 disruptive_inframe_insertion
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.299
• Publications: 2 publications found

Genes affected

PHC1 (HGNC:3182): (polyhomeotic homolog 1) This gene is a homolog of the Drosophila polyhomeotic gene, which is a member of the Polycomb group of genes. The gene product is a component of a multimeric protein complex that contains EDR2 and the vertebrate Polycomb protein BMH1. The gene product, the EDR2 protein, and the Drosophila polyhomeotic protein share 2 highly conserved domains, named homology domains I and II. These domains are involved in protein-protein interactions and may mediate heterodimerization of the protein encoded by this gene and the EDR2 protein. [provided by RefSeq, Jul 2008]

PHC1 Gene-Disease associations (from GenCC):

• autosomal recessive primary microcephaly

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• microcephaly 11, primary, autosomal recessive

  Inheritance: AR Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae), G2P

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM4: Nonframeshift variant in NON repetitive region in NM_004426.3. Strenght limited to Supporting due to length of the change: 1aa.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PHC1	NM_004426.3	c.1287_1289dupGCA	p.Gln430dup	disruptive_inframe_insertion	Exon 8 of 15	ENST00000544916.6	NP_004417.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PHC1	ENST00000544916.6	c.1287_1289dupGCA	p.Gln430dup	disruptive_inframe_insertion	Exon 8 of 15	1	NM_004426.3	ENSP00000437659.1

Frequencies

GnomAD3 genomes AF: 0.000672 AC: 102 AN: 151858 Hom.: 0 Cov.: 27

Gnomad AFR AF: 0.00236

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000192

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000441

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.000254 AC: 63 AN: 248330 AF XY: 0.000223

Gnomad AFR exome AF: 0.00282

Gnomad AMR exome AF: 0.000146

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000546

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000267

Gnomad OTH exome AF: 0.000493

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.000114 AC: 166 AN: 1460894 Hom.: 0 Cov.: 32 AF XY: 0.000118 AC XY: 86 AN XY: 726738

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

African (AFR) AF: 0.00273 AC: 91 AN: 33390

American (AMR) AF: 0.000134 AC: 6 AN: 44702

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26124

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

South Asian (SAS) AF: 0.000232 AC: 20 AN: 86214

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.000174 AC: 1 AN: 5756

European-Non Finnish (NFE) AF: 0.0000297 AC: 33 AN: 1111248

Other (OTH) AF: 0.000249 AC: 15 AN: 60346

⚠️ 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: 0.000678 AC: 103 AN: 151974 Hom.: 0 Cov.: 27 AF XY: 0.000660 AC XY: 49 AN XY: 74282

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

African (AFR) AF: 0.00237 AC: 98 AN: 41290

American (AMR) AF: 0.0000654 AC: 1 AN: 15280

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.000193 AC: 1 AN: 5188

South Asian (SAS) AF: 0.00 AC: 0 AN: 4822

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10620

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000441 AC: 3 AN: 67990

Other (OTH) AF: 0.00 AC: 0 AN: 2110

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.0000800 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		-0.30
Mutation Taster		=72/28	polymorphism

Splicing

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

Other links and lift over

dbSNP: rs368945524; hg19: chr12-9085324;