Co-occurrence of a maternally inherited DNMT3A duplication and a paternally inherited pathogenic variant in EZH2 in a child with growth retardation and severe short stature: atypical Weaver syndrome or evidence of a DNMT3A dosage effect? Cold Spring Harb Mol Case Stud 2018 Aug;4(4)
Date
05/29/2018Pubmed ID
29802153Pubmed Central ID
PMC6071565DOI
10.1101/mcs.a002899Scopus ID
2-s2.0-85054778837 (requires institutional sign-in at Scopus site) 8 CitationsAbstract
Overgrowth syndromes are a clinically heterogeneous group of disorders characterized by localized or generalized tissue overgrowth and varying degrees of developmental and intellectual disability. An expanding list of genes associated with overgrowth syndromes include the histone methyltransferase genes EZH2 and NSD1, which cause Weaver and Sotos syndrome, respectively, and the DNA methyltransferase (DNMT3A) gene that results in Tatton-Brown-Rahman syndrome (TBRS). Here, we describe a 5-year-old female with a paternally inherited pathogenic mutation in EZH2 (c.2050C>T, p.Arg684Cys) and a maternally inherited 505-kb duplication of uncertain significance at 2p23.3 (encompassing five genes, including DNMT3A) who presented with intrauterine growth restriction, slow postnatal growth, short stature, hypotonia, developmental delay, and neuroblastoma diagnosed at the age of 8 mo. Her father had tall stature, dysmorphic facial features, and intellectual disability consistent with Weaver syndrome, whereas her mother had short stature, cognitive delays, and chronic nonprogressive leukocytosis. It has been previously shown that EZH2 directly controls DNA methylation through physical association with DNMTs, including DNMT3A, with concomitant H3K27 methylation and CpG promoter methylation leading to repression of EZH2 target genes. Interestingly, NSD1 is involved in H3K36 methylation, a mark associated with transcriptional activation, and exhibits exquisite dosage sensitivity leading to overgrowth when deleted and severe undergrowth when duplicated in vivo. Although there is currently no evidence of dosage effects for DNMT3A, the co-occurrence of a duplication involving this gene and a pathogenic alteration in EZH2 in a patient with severe undergrowth is suggestive of a similar paradigm and further study is warranted.
Author List
Polonis K, Blackburn PR, Urrutia RA, Lomberk GA, Kruisselbrink T, Cousin MA, Boczek NJ, Hoppman NL, Babovic-Vuksanovic D, Klee EW, Pichurin PNAuthors
Gwen Lomberk PhD Professor in the Surgery department at Medical College of WisconsinRaul A. Urrutia MD Center Director, Professor in the Surgery department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
Abnormalities, MultipleAdult
Child
Congenital Hypothyroidism
Craniofacial Abnormalities
DNA (Cytosine-5-)-Methyltransferases
Enhancer of Zeste Homolog 2 Protein
Female
Gene Dosage
Gene Duplication
Hand Deformities, Congenital
Humans
Male
Pedigree
Phenotype
