chr15-40623048-T-C

Variant names:

• chr15-40623048-T-C
• rs587780293
• NM_144508.5:c.2784T>C

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_144508.5(KNL1):​c.2784T>C​(p.Thr928Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000616 in 1,461,730 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: not found (cov: 32)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: KNL1 NM_144508.5 synonymous
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.06
• 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: Labcorp Genetics (formerly Invitae), Ambry Genetics
• autosomal recessive primary microcephaly

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.83).
• BP7: Synonymous conserved (PhyloP=1.06 with no splicing effect.

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KNL1	NM_144508.5	MANE Select	c.2784T>C	p.Thr928Thr	synonymous	Exon 10 of 26	NP_653091.3	Q8NG31-2
	KNL1	NM_170589.5		c.2862T>C	p.Thr954Thr	synonymous	Exon 11 of 27	NP_733468.3	Q8NG31-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KNL1	ENST00000399668.7	TSL:1 MANE Select	c.2784T>C	p.Thr928Thr	synonymous	Exon 10 of 26	ENSP00000382576.3	Q8NG31-2
	KNL1	ENST00000346991.9	TSL:1	c.2862T>C	p.Thr954Thr	synonymous	Exon 11 of 27	ENSP00000335463.6	Q8NG31-1
	KNL1	ENST00000533001.1	TSL:1	n.2929T>C		non_coding_transcript_exon	Exon 10 of 10

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461730 Hom.: 0 Cov.: 41 AF XY: 0.00000550 AC XY: 4 AN XY: 727166

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39684

South Asian (SAS) AF: 0.00 AC: 0 AN: 86246

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000809 AC: 9 AN: 1111910

Other (OTH) AF: 0.00 AC: 0 AN: 60384

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	7.5
DANN	Benign	0.66
PhyloP100		1.1

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: rs587780293; hg19: chr15-40915246;