1-113904680-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_001253852.3(AP4B1):c.38T>C(p.Leu13Pro) 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. 13/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L13M) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: AP4B1 NM_001253852.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.92

Genes affected

AP4B1 (HGNC:572): (adaptor related protein complex 4 subunit beta 1) This gene encodes a subunit of a heterotetrameric adapter-like complex 4 that is involved in targeting proteins from the trans-Golgi network to the endosomal-lysosomal system. Mutations in this gene are associated with cerebral palsy spastic quadriplegic type 5 (CPSQ5) disorder. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2011]

DCLRE1B (HGNC:17641): (DNA cross-link repair 1B) DNA interstrand cross-links prevent strand separation, thereby physically blocking transcription, replication, and segregation of DNA. DCLRE1B is one of several evolutionarily conserved genes involved in repair of interstrand cross-links (Dronkert et al., 2000 [PubMed 10848582]).[supplied by OMIM, Mar 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.916

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AP4B1	NM_001253852.3	c.38T>C	p.Leu13Pro	missense_variant	1/10	ENST00000369569.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AP4B1	ENST00000369569.6	c.38T>C	p.Leu13Pro	missense_variant	1/10	1	NM_001253852.3	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 22, 2021

The c.38T>C (p.L13P) alteration is located in exon 2 (coding exon 1) of the AP4B1 gene. This alteration results from a T to C substitution at nucleotide position 38, causing the leucine (L) at amino acid position 13 to be replaced by a proline (P). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.33
Cadd	Pathogenic	32
Dann	Pathogenic	1.0
DEOGEN2	Benign	0.28	T;D;D;T;T;T
Eigen	Pathogenic	0.85
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Benign	0.75	D
LIST_S2	Uncertain	0.86	D;.;D;D;D;D
M_CAP	Uncertain	0.17	D
MetaRNN	Pathogenic	0.92	D;D;D;D;D;D
MetaSVM	Uncertain	0.35	D
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.86	D
PROVEAN	Benign	-1.8	N;D;D;D;N;D
REVEL	Pathogenic	0.69
Sift	Pathogenic	0.0	D;D;D;D;D;D
Sift4G	Benign	0.083	T;D;D;.;.;.
Polyphen		1.0	D;D;D;.;.;.
Vest4		0.92
MutPred		0.83		Gain of disorder (P = 0.0126);Gain of disorder (P = 0.0126);Gain of disorder (P = 0.0126);Gain of disorder (P = 0.0126);Gain of disorder (P = 0.0126);Gain of disorder (P = 0.0126);
MVP		0.93
MPC		0.73
ClinPred		0.96	D
GERP RS		5.3
Varity_R		0.99
gMVP		0.86

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-114447302;