13-99985448-AGCGGCGGCG-AGCGGCGGCGGCG

Variant names:

• chr13-99985448-A-AGCG
• rs749567106
• NM_007129.5:c.1374_1376dupGGC

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP3 BS2

The NM_007129.5(ZIC2):​c.1374_1376dupGGC​(p.Ala459dup) variant causes a disruptive inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000142 in 1,266,630 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: ZIC2 NM_007129.5 disruptive_inframe_insertion
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.50

Genes affected

ZIC2 (HGNC:12873): (Zic family member 2) This gene encodes a member of the ZIC family of C2H2-type zinc finger proteins. This protein functions as a transcriptional repressor and may regulate tissue specific expression of dopamine receptor D1. Expansion of an alanine repeat in the C-terminus of the encoded protein and other mutations in this gene cause holoprosencephaly type 5. Holoprosencephaly is the most common structural anomaly of the human brain. A polyhistidine tract polymorphism in this gene may be associated with increased risk of neural tube defects. This gene is closely linked to a gene encoding zinc finger protein of the cerebellum 5, a related family member on chromosome 13. [provided by RefSeq, Jul 2016]

ACMG classification

Verdict is Likely_benign. Variant got -5 ACMG points.

• BP3: Nonframeshift variant in repetitive region in NM_007129.5
• BS2: High AC in GnomAdExome4 at 18 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ZIC2	NM_007129.5	c.1374_1376dupGGC	p.Ala459dup	disruptive_inframe_insertion	Exon 3 of 3	ENST00000376335.8	NP_009060.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ZIC2	ENST00000376335.8	c.1374_1376dupGGC	p.Ala459dup	disruptive_inframe_insertion	Exon 3 of 3	1	NM_007129.5	ENSP00000365514.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.0000142 AC: 18 AN: 1266630 Hom.: 0 Cov.: 31 AF XY: 0.0000128 AC XY: 8 AN XY: 624118

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000195

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000166

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Holoprosencephaly 5 Uncertain:1

Apr 10, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant, c.1374_1376dup, results in the insertion of 1 amino acid(s) of the ZIC2 protein (p.Ala470dup), but otherwise preserves the integrity of the reading frame. This variant is not present in population databases (gnomAD no frequency). This variant has been observed in individual(s) with holoprosencephaly (PMID: 21940735). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs749567106; hg19: chr13-100637702;