1-197084243-G-T

Variant names:

• chr1-197084243-G-T
• rs12677
• ENST00000367408.6:n.3802C>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The ENST00000367408.6(ASPM):​n.3802C>A variant causes a non coding transcript exon change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000114 in 878,098 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.

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 0.0000011 (0 hom.)
• Consequence: ASPM ENST00000367408.6 non_coding_transcript_exon
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.02
• Publications: 0 publications found

Genes affected

ASPM (HGNC:19048): (assembly factor for spindle microtubules) This gene is the human ortholog of the Drosophila melanogaster 'abnormal spindle' gene (asp), which is essential for normal mitotic spindle function in embryonic neuroblasts. Studies in mouse also suggest a role of this gene in mitotic spindle regulation, with a preferential role in regulating neurogenesis. Mutations in this gene are associated with microcephaly primary type 5. Multiple transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, May 2011]

ASPM Gene-Disease associations (from GenCC):

• microcephaly 5, primary, autosomal recessive

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• autosomal recessive primary microcephaly

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ASPM	NM_018136.5	c.*81C>A		3_prime_UTR_variant	Exon 28 of 28	ENST00000367409.9	NP_060606.3
ASPM	NM_001206846.2	c.*81C>A		3_prime_UTR_variant	Exon 27 of 27		NP_001193775.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ASPM	ENST00000367409.9	c.*81C>A		3_prime_UTR_variant	Exon 28 of 28	1	NM_018136.5	ENSP00000356379.4

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome AF: 0.00000114 AC: 1 AN: 878098 Hom.: 0 Cov.: 11 AF XY: 0.00000219 AC XY: 1 AN XY: 457620

⚠️ 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: 21418

American (AMR) AF: 0.00 AC: 0 AN: 39650

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 22058

East Asian (EAS) AF: 0.00 AC: 0 AN: 36186

South Asian (SAS) AF: 0.0000141 AC: 1 AN: 71064

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 46472

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4444

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 595676

Other (OTH) AF: 0.00 AC: 0 AN: 41130

⚠️ 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.: 30

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	1.5
DANN	Benign	0.48
PhyloP100		3.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0

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: rs12677; hg19: chr1-197053373;