chr4-41747488-T-G

Variant names:

• chr4-41747488-T-G
• rs1060501123
• NM_003924.4:c.290A>C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_003924.4(PHOX2B):​c.290A>C​(p.Lys97Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: PHOX2B NM_003924.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.97
• Publications: 0 publications found

Genes affected

PHOX2B (HGNC:9143): (paired like homeobox 2B) The DNA-associated protein encoded by this gene is a member of the paired family of homeobox proteins localized to the nucleus. The protein functions as a transcription factor involved in the development of several major noradrenergic neuron populations and the determination of neurotransmitter phenotype. The gene product is linked to enhancement of second messenger-mediated activation of the dopamine beta-hydroylase, c-fos promoters and several enhancers, including cyclic amp-response element and serum-response element. Expansion of a 20 amino acid polyalanine tract in this protein by 5-13 aa has been associated with congenital central hypoventilation syndrome. [provided by RefSeq, Jul 2016]

PHOX2B Gene-Disease associations (from GenCC):

• central hypoventilation syndrome, congenital, 1, with or without Hirschsprung disease

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, G2P
• Haddad syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• neuroblastoma, susceptibility to, 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P
• congenital central hypoventilation syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 26 uncertain in NM_003924.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.877

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003924.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PHOX2B	NM_003924.4	MANE Select	c.290A>C	p.Lys97Thr	missense	Exon 2 of 3	NP_003915.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PHOX2B	ENST00000226382.4	TSL:1 MANE Select	c.290A>C	p.Lys97Thr	missense	Exon 2 of 3	ENSP00000226382.2
	PHOX2B	ENST00000510424.2	TSL:3	n.111A>C		non_coding_transcript_exon	Exon 2 of 3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Haddad syndrome Uncertain:1

Jun 21, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces lysine with threonine at codon 97 of the PHOX2B protein (p.Lys97Thr). The lysine residue is highly conserved and there is a moderate physicochemical difference between lysine and threonine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with PHOX2B-related disease. ClinVar contains an entry for this variant (Variation ID: 406407). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance.

Hereditary cancer-predisposing syndrome Uncertain:1

Aug 09, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.K97T variant (also known as c.290A>C), located in coding exon 2 of the PHOX2B gene, results from an A to C substitution at nucleotide position 290. The lysine at codon 97 is replaced by threonine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.21
CADD	Pathogenic	31
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.79	D
Eigen	Uncertain	0.47
Eigen_PC	Uncertain	0.54
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.93	D
M_CAP	Uncertain	0.21	D
MetaRNN	Pathogenic	0.88	D
MetaSVM	Benign	-0.44	T
MutationAssessor	Uncertain	2.2	M
PhyloP100		8.0
PrimateAI	Pathogenic	0.91	D
PROVEAN	Pathogenic	-5.6	D
REVEL	Pathogenic	0.83
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0020	D
Polyphen		1.0	D
Vest4		0.79
MutPred		0.46		Gain of phosphorylation at K97 (P = 0.0318)
MVP		0.93
MPC		2.5
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.90
gMVP		0.96
Mutation Taster		=37/63	disease causing

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: rs1060501123; hg19: chr4-41749505;