11-66744819-GGGCGGCGGCGGCGGC-GGGCGGCGGCGGCGGCGGCGGC

Variant names:

• chr11-66744832-GG-GGCGGCG
• NM_001302084.2:c.-115_-111dupCGGCG

Variant summary

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

The NM_001302084.2(TOP6BL):​c.-115_-111dupCGGCG variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 31)
• Consequence: TOP6BL NM_001302084.2 5_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.974
• Publications: 0 publications found

Genes affected

TOP6BL (HGNC:26197): (TOP6B like initiator of meiotic double strand breaks) Predicted to be involved in meiotic DNA double-strand break formation and reciprocal meiotic recombination. Predicted to be located in chromosome. Implicated in gestational trophoblastic neoplasm. [provided by Alliance of Genome Resources, Apr 2022]

SPTBN2 (HGNC:11276): (spectrin beta, non-erythrocytic 2) Spectrins are principle components of a cell's membrane-cytoskeleton and are composed of two alpha and two beta spectrin subunits. The protein encoded by this gene (SPTBN2), is called spectrin beta non-erythrocytic 2 or beta-III spectrin. It is related to, but distinct from, the beta-II spectrin gene which is also known as spectrin beta non-erythrocytic 1 (SPTBN1). SPTBN2 regulates the glutamate signaling pathway by stabilizing the glutamate transporter EAAT4 at the surface of the plasma membrane. Mutations in this gene cause a form of spinocerebellar ataxia, SCA5, that is characterized by neurodegeneration, progressive locomotor incoordination, dysarthria, and uncoordinated eye movements. [provided by RefSeq, Dec 2009]

SPTBN2 Gene-Disease associations (from GenCC):

• spinocerebellar ataxia type 5

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, ClinGen, G2P, Orphanet, Labcorp Genetics (formerly Invitae), Illumina
• autosomal recessive spinocerebellar ataxia 14

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, G2P, Orphanet, Labcorp Genetics (formerly Invitae)

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_001302084.2. 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
	TOP6BL	NM_001302084.2	MANE Select	c.-115_-111dupCGGCG		5_prime_UTR	Exon 1 of 15	NP_001289013.1	Q8N6T0-6
	TOP6BL	NM_024650.4		c.-56_-52dupCGGCG		5_prime_UTR	Exon 1 of 17	NP_078926.4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TOP6BL	ENST00000540737.7	TSL:2 MANE Select	c.-115_-111dupCGGCG		5_prime_UTR	Exon 1 of 15	ENSP00000444319.1	Q8N6T0-6
	TOP6BL	ENST00000525908.6	TSL:2	c.-56_-52dupCGGCG		5_prime_UTR	Exon 1 of 17	ENSP00000432039.3	A0A2U3TZP7
	TOP6BL	ENST00000901160.1		c.-115_-111dupCGGCG		5_prime_UTR	Exon 1 of 15	ENSP00000571219.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		-0.97

Splicing

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr11-66512303;