chr14-64804932-A-T

Variant names:

• chr14-64804932-A-T
• rs229581
• NM_001355436.2:c.300+7T>A

Variant summary

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

The NM_001355436.2(SPTB):​c.300+7T>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,638 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SPTB NM_001355436.2 splice_region, intron
• Scores: Splicing: ADA: 0.00003127
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.457
• Publications: 6 publications found

Genes affected

SPTB (HGNC:11274): (spectrin beta, erythrocytic) This locus encodes a member of the spectrin gene family. Spectrin proteins, along with ankyrin, play a role in cell membrane organization and stability. The protein encoded by this locus functions in stability of erythrocyte membranes, and mutations in this gene have been associated with spherocytosis type 2, hereditary elliptocytosis, and neonatal hemolytic anemia. Alternatively spliced transcript variants have been described. [provided by RefSeq, Nov 2009]

SPTB Gene-Disease associations (from GenCC):

• hereditary spherocytosis type 2

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• elliptocytosis 3

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• hereditary elliptocytosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hereditary spherocytosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

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=-0.83).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SPTB	NM_001355436.2	c.300+7T>A		splice_region_variant, intron_variant	Intron 3 of 35	ENST00000644917.1	NP_001342365.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SPTB	ENST00000644917.1	c.300+7T>A		splice_region_variant, intron_variant	Intron 3 of 35		NM_001355436.2	ENSP00000495909.1
SPTB	ENST00000389722.7	c.300+7T>A		splice_region_variant, intron_variant	Intron 2 of 34	2		ENSP00000374372.3
SPTB	ENST00000389720.4	c.300+7T>A		splice_region_variant, intron_variant	Intron 3 of 31	5		ENSP00000374370.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461638 Hom.: 0 Cov.: 46 AF XY: 0.00 AC XY: 0 AN XY: 727126

⚠️ 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: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.0000383 AC: 1 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53404

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5626

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111970

Other (OTH) AF: 0.00 AC: 0 AN: 60366

⚠️ 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.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	5.3
DANN	Benign	0.46
PhyloP100		0.46

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000031
dbscSNV1_RF	Benign	0.0
SpliceAI score (max)		0.040		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: rs229581; hg19: chr14-65271650;