2-85657559-G-T

Variant names:

• chr2-85657559-G-T
• rs546289871
• NM_000542.5:c.*2143C>A

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_Strong BS1_Supporting

The NM_000542.5(SFTPB):​c.*2143C>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000466 in 152,282 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00047 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SFTPB NM_000542.5 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.20
• Publications: 0 publications found

Genes affected

SFTPB (HGNC:10801): (surfactant protein B) This gene encodes the pulmonary-associated surfactant protein B (SPB), an amphipathic surfactant protein essential for lung function and homeostasis after birth. Pulmonary surfactant is a surface-active lipoprotein complex composed of 90% lipids and 10% proteins which include plasma proteins and apolipoproteins SPA, SPB, SPC and SPD. The surfactant is secreted by the alveolar cells of the lung and maintains the stability of pulmonary tissue by reducing the surface tension of fluids that coat the lung. The SPB enhances the rate of spreading and increases the stability of surfactant monolayers in vitro. Multiple mutations in this gene have been identified, which cause pulmonary surfactant metabolism dysfunction type 1, also called pulmonary alveolar proteinosis due to surfactant protein B deficiency, and are associated with fatal respiratory distress in the neonatal period. Alternatively spliced transcript variants encoding the same protein have been identified.[provided by RefSeq, Feb 2010]

USP39 (HGNC:20071): (ubiquitin specific peptidase 39) Predicted to enable thiol-dependent deubiquitinase and zinc ion binding activity. Involved in spliceosomal complex assembly. Located in nucleoplasm. Part of U4/U6 x U5 tri-snRNP complex. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.93).
• BS1: Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000466 (71/152282) while in subpopulation NFE AF = 0.000882 (60/68018). AF 95% confidence interval is 0.000703. There are 0 homozygotes in GnomAd4. There are 30 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000542.5. 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
	SFTPB	NM_000542.5	MANE Select	c.*2143C>A		3_prime_UTR	Exon 11 of 11	NP_000533.4
	SFTPB	NM_198843.3		c.*1316C>A		3_prime_UTR	Exon 12 of 12	NP_942140.3	P07988
	SFTPB	NM_001367281.1		c.*1222C>A		3_prime_UTR	Exon 9 of 9	NP_001354210.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SFTPB	ENST00000519937.7	TSL:1 MANE Select	c.*2143C>A		3_prime_UTR	Exon 11 of 11	ENSP00000428719.2	P07988
	SFTPB	ENST00000393822.7	TSL:1	c.*2143C>A		3_prime_UTR	Exon 12 of 12	ENSP00000377409.4	P07988
	SFTPB	ENST00000409383.7	TSL:1	c.*1316C>A		3_prime_UTR	Exon 12 of 12	ENSP00000386346.2

Frequencies

GnomAD3 genomes AF: 0.000473 AC: 72 AN: 152164 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000193

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000897

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 8 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 6

African (AFR) AC: 0 AN: 0

American (AMR) AC: 0 AN: 0

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 2

East Asian (EAS) AC: 0 AN: 0

South Asian (SAS) AC: 0 AN: 0

European-Finnish (FIN) AC: 0 AN: 0

Middle Eastern (MID) AC: 0 AN: 0

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 4

Other (OTH) AF: 0.00 AC: 0 AN: 2

GnomAD4 genome AF: 0.000466 AC: 71 AN: 152282 Hom.: 0 Cov.: 32 AF XY: 0.000403 AC XY: 30 AN XY: 74458

African (AFR) AF: 0.000192 AC: 8 AN: 41566

American (AMR) AF: 0.0000654 AC: 1 AN: 15292

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5176

South Asian (SAS) AF: 0.000414 AC: 2 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10612

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.000882 AC: 60 AN: 68018

Other (OTH) AF: 0.00 AC: 0 AN: 2112

Alfa AF: 0.000208 Hom.: 0

Bravo AF: 0.000446

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Surfactant metabolism dysfunction, pulmonary, 1 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.93
CADD	Benign	0.20
DANN	Benign	0.42
PhyloP100		-1.2
Mutation Taster		=100/0	polymorphism

Splicing

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

Other links and lift over

dbSNP: rs546289871; hg19: chr2-85884682;