19-2430939-G-T

Variant names:

• chr19-2430939-G-T
• rs1264803988
• NM_032737.4:c.1835C>A

Variant summary

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

The NM_032737.4(LMNB2):​c.1835C>A​(p.Thr612Asn) variant causes a missense change. The variant allele was found at a frequency of 0.000000686 in 1,457,534 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T612I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: LMNB2 NM_032737.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.07
• Publications: 0 publications found

Genes affected

LMNB2 (HGNC:6638): (lamin B2) This gene encodes a B type nuclear lamin. The nuclear lamina consists of a two-dimensional matrix of proteins located next to the inner nuclear membrane. The lamin family of proteins make up the matrix and are highly conserved in evolution. During mitosis, the lamina matrix is reversibly disassembled as the lamin proteins are phosphorylated. Lamin proteins are thought to be involved in nuclear stability, chromatin structure and gene expression. Vertebrate lamins consist of two types, A and B. Mutations in this gene are associated with acquired partial lipodystrophy. [provided by RefSeq, May 2012]

LMNB2 Gene-Disease associations (from GenCC):

• microcephaly 27, primary, autosomal dominant

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• progressive myoclonic epilepsy type 9

  Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae)
• microcephaly

  Inheritance: AD Classification: MODERATE Submitted by: Franklin by Genoox
• lipodystrophy, partial, acquired, susceptibility to

  Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• central nervous system malformation

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

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_032737.4. 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
	LMNB2	NM_032737.4	MANE Select	c.1835C>A	p.Thr612Asn	missense	Exon 12 of 12	NP_116126.3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LMNB2	ENST00000325327.4	TSL:1 MANE Select	c.1835C>A	p.Thr612Asn	missense	Exon 12 of 12	ENSP00000327054.3	Q03252
	LMNB2	ENST00000917224.1		c.1976C>A	p.Thr659Asn	missense	Exon 13 of 13	ENSP00000587283.1
	LMNB2	ENST00000917223.1		c.1841C>A	p.Thr614Asn	missense	Exon 12 of 12	ENSP00000587282.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1457534 Hom.: 0 Cov.: 28 AF XY: 0.00 AC XY: 0 AN XY: 725332

African (AFR) AF: 0.00 AC: 0 AN: 33376

American (AMR) AF: 0.00 AC: 0 AN: 44716

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26106

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86144

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53378

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5580

European-Non Finnish (NFE) AF: 9.02e-7 AC: 1 AN: 1108322

Other (OTH) AF: 0.00 AC: 0 AN: 60220

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Uncertain	0.056	T
BayesDel_noAF	Benign	-0.16
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Benign	0.29	T
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.87	D
M_CAP	Benign	0.055	D
MetaRNN	Uncertain	0.45	T
MetaSVM	Benign	-0.66	T
PhyloP100		6.1
PrimateAI	Uncertain	0.71	T
REVEL	Benign	0.13
Sift4G	Benign	0.49	T
Vest4		0.51
MVP		0.57
MPC		0.87
ClinPred		0.97	D
GERP RS		3.9
Varity_R		0.095
gMVP		0.15
Mutation Taster		=86/14	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
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: rs1264803988; hg19: chr19-2430937;