NM_144508.5:c.6172+5T>C

Variant names:

• chr15-40650383-T-C
• rs769654305
• NM_144508.5:c.6172+5T>C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_144508.5(KNL1):​c.6172+5T>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000497 in 1,608,184 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 Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: KNL1 NM_144508.5 splice_region, intron
• Scores: Splicing: ADA: 0.00004145
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.342
• Publications: 0 publications found

Genes affected

KNL1 (HGNC:24054): (kinetochore scaffold 1) The protein encoded by this gene is a component of the multiprotein assembly that is required for creation of kinetochore-microtubule attachments and chromosome segregation. The encoded protein functions as a scaffold for proteins that influence the spindle assembly checkpoint during the eukaryotic cell cycle and it interacts with at least five different kinetochore proteins and two checkpoint kinases. In adults, this gene is predominantly expressed in normal testes, various cancer cell lines and primary tumors from other tissues and is ubiquitously expressed in fetal tissues. This gene was originally identified as a fusion partner with the mixed-lineage leukemia (MLL) gene in t(11;15)(q23;q14). Mutations in this gene cause autosomal recessive primary microcephaly-4 (MCPH4). Alternative splicing results in multiple transcript variants encoding different isoforms. Additional splice variants have been described but their biological validity has not been confirmed. [provided by RefSeq, Jan 2013]

KNL1 Gene-Disease associations (from GenCC):

• microcephaly 4, primary, autosomal recessive

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• autosomal recessive primary microcephaly

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.74).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_144508.5. 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
	KNL1	NM_144508.5	MANE Select	c.6172+5T>C		splice_region intron	N/A	NP_653091.3
	KNL1	NM_170589.5		c.6250+5T>C		splice_region intron	N/A	NP_733468.3

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KNL1	ENST00000399668.7	TSL:1 MANE Select	c.6172+5T>C		splice_region intron	N/A	ENSP00000382576.3
	KNL1	ENST00000346991.9	TSL:1	c.6250+5T>C		splice_region intron	N/A	ENSP00000335463.6
	KNL1	ENST00000526913.5	TSL:1	n.3304+5T>C		splice_region intron	N/A	ENSP00000432565.1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152154 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000724

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000401 AC: 1 AN: 249138 AF XY: 0.00000740

Gnomad AFR exome AF: 0.0000646

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000343 AC: 5 AN: 1456030 Hom.: 0 Cov.: 28 AF XY: 0.00000276 AC XY: 2 AN XY: 724766

African (AFR) AF: 0.0000600 AC: 2 AN: 33358

American (AMR) AF: 0.00 AC: 0 AN: 44670

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26084

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39628

South Asian (SAS) AF: 0.00 AC: 0 AN: 86032

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5752

European-Non Finnish (NFE) AF: 0.00000181 AC: 2 AN: 1106918

Other (OTH) AF: 0.00 AC: 0 AN: 60180

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152154 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74320

African (AFR) AF: 0.0000724 AC: 3 AN: 41448

American (AMR) AF: 0.00 AC: 0 AN: 15258

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5200

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10602

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68028

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00000812 Hom.: 0

Bravo AF: 0.0000189

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Oct 05, 2015

Genetic Services Laboratory, University of Chicago

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.74
CADD	Benign	12
DANN	Benign	0.86
PhyloP100		-0.34
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000041
dbscSNV1_RF	Benign	0.028
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: rs769654305; hg19: chr15-40942581;