Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong
The NM_024596.5(MCPH1):c.-39G>C variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000249 in 1,608,526 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.
MCPH1 (HGNC:6954): (microcephalin 1) This gene encodes a DNA damage response protein. The encoded protein may play a role in G2/M checkpoint arrest via maintenance of inhibitory phosphorylation of cyclin-dependent kinase 1. Mutations in this gene have been associated with primary autosomal recessive microcephaly 1 and premature chromosome condensation syndrome. Alternatively spliced transcript variants have been described. [provided by RefSeq, Feb 2010]
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000601
AC:
2
AN:
33292
American (AMR)
AF:
0.00
AC:
0
AN:
44390
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25908
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39506
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85544
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51744
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5634
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1110250
Other (OTH)
AF:
0.00
AC:
0
AN:
60078
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.