chr7-33177472-C-A

Variant names:

• chr7-33177472-C-A
• rs1445078208
• NM_198428.3:c.329-6C>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP6

The NM_198428.3(BBS9):​c.329-6C>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 0.00000756 in 1,322,714 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. Variant has been reported in ClinVar as Likely benign (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000076 (0 hom.)
• Consequence: BBS9 NM_198428.3 splice_region, intron
• Scores: Splicing: ADA: 0.0003498
• Clinical Significance: Likely benign no assertion criteria provided B:1
• Conservation: PhyloP100: -0.156
• Publications: 0 publications found

Genes affected

BBS9 (HGNC:30000): (Bardet-Biedl syndrome 9) This gene is downregulated by parathyroid hormone in osteoblastic cells, and therefore is thought to be involved in parathyroid hormone action in bones. The exact function of this gene has not yet been determined. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jan 2017]

BBS9 Gene-Disease associations (from GenCC):

• Bardet-Biedl syndrome 9

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• ciliopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• Bardet-Biedl syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.74).
• BP6: Variant 7-33177472-C-A is Benign according to our data. Variant chr7-33177472-C-A is described in ClinVar as Likely_benign. ClinVar VariationId is 3058465.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_198428.3. 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
	BBS9	NM_198428.3	MANE Select	c.329-6C>A		splice_region intron	N/A	NP_940820.1
	BBS9	NM_001348041.4		c.329-6C>A		splice_region intron	N/A	NP_001334970.1
	BBS9	NM_001348036.1		c.329-6C>A		splice_region intron	N/A	NP_001334965.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BBS9	ENST00000242067.11	TSL:1 MANE Select	c.329-6C>A		splice_region intron	N/A	ENSP00000242067.6
	BBS9	ENST00000425508.6	TSL:1	c.194-6C>A		splice_region intron	N/A	ENSP00000405151.2
	BBS9	ENST00000433714.5	TSL:1	n.329-6C>A		splice_region intron	N/A	ENSP00000412159.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000756 AC: 10 AN: 1322714 Hom.: 0 Cov.: 27 AF XY: 0.00000302 AC XY: 2 AN XY: 661482

⚠️ 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: 29028

American (AMR) AF: 0.00 AC: 0 AN: 36842

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 24004

East Asian (EAS) AF: 0.00 AC: 0 AN: 37390

South Asian (SAS) AF: 0.00 AC: 0 AN: 75996

European-Finnish (FIN) AF: 0.0000206 AC: 1 AN: 48642

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5310

European-Non Finnish (NFE) AF: 0.00000890 AC: 9 AN: 1010712

Other (OTH) AF: 0.00 AC: 0 AN: 54790

⚠️ 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

ClinVar submissions as Germline

Significance: Likely benign

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
-	-	1	BBS9-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.74
CADD	Benign	3.2
DANN	Benign	0.72
PhyloP100		-0.16

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00035
dbscSNV1_RF	Benign	0.096
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: rs1445078208; hg19: chr7-33217084;