Question: Is Weaver syndrome similar to Sotos?

Context:
Overgrowth conditions are a heterogeneous group of disorders characterised by increased growth and variable features, including macrocephaly, distinctive facial appearance and various degrees of learning difficulties and intellectual disability. Among them, Sotos and Weaver syndromes are clinically well defined and due to heterozygous mutations in NSD1 and EZH2, respectively. NSD1 and EZH2 are both histone-modifying enzymes
NSD1 and EZH2 are SET domain-containing histone methyltransferases that play key roles in the regulation of transcription through histone modification and chromatin modeling: NSD1 preferentially methylates lysine residue 36 of histone 3 (H3K36) and is primarily associated with active transcription, while EZH2 shows specificity for lysine residue 27 (H3K27) and is associated with transcriptional repression
Constitutional NSD1 and EZH2 mutations cause Sotos and Weaver syndromes respectively, overgrowth syndromes with considerable phenotypic overlap
Clinically, Weaver syndrome is closely related to Sotos syndrome, which is frequently caused by mutations in NSD1
Overgrowth syndromes such as Beckwith-Wiedemann syndrome, Sotos syndrome, and Weaver syndrome have an increased risk of neoplasia.
Thus, it is not surprising that prenatal overgrowth occurs in several syndromes, including the Sotos and Weaver syndromes.
NSD1 mutations are the major cause of Sotos syndrome and occur in some cases of Weaver syndrome but are rare in other overgrowth phenotypes.
We conclude therefore that NSD1 mutations account for most cases of Sotos syndrome and a significant number of Weaver syndrome cases in our series.
We conclude that intragenic mutations of NSD1 are the major cause of Sotos syndrome and account for some Weaver syndrome cases but rarely occur in other childhood overgrowth phenotypes.
Overgrowth syndromes such as Beckwith-Wiedemann syndrome, Sotos syndrome, and Weaver syndrome have an increased risk of neoplasia
NSD1 mutations are the major cause of Sotos syndrome and occur in some cases of Weaver syndrome but are rare in other overgrowth phenotypes
We conclude that intragenic mutations of NSD1 are the major cause of Sotos syndrome and account for some Weaver syndrome cases but rarely occur in other childhood overgrowth phenotypes
Considerable phenotypic overlap between Sotos and Weaver syndromes is also evident. 
Considerable phenotypic overlap between Sotos and Weaver syndromes is also evident. The identification of an EZH2 mutation can therefore provide an objective means of confirming a subtle presentation of Weaver syndrome and/or distinguishing Weaver and Sotos syndromes.
 Overgrowth syndromes such as Beckwith-Wiedemann syndrome, Sotos syndrome, and Weaver syndrome have an increased risk of neoplasia. Two previous cases of neuroblastoma have been reported in children with Weaver syndrome.
Weaver syndrome is closely related to Sotos syndrome,
Overgrowth syndromes such as Beckwith-Wiedemann syndrome, Sotos syndrome, and Weaver syndrome have an increased risk of neoplasia.
Considerable phenotypic overlap between Sotos and Weaver syndromes is also evident.
Clinically, Weaver syndrome is closely related to Sotos syndrome, which is frequently caused by mutations in NSD1.

Answer: Overgrowth conditions are a heterogeneous group of disorders characterised by increased growth and variable features, including macrocephaly, distinctive facial appearance and various degrees of learning difficulties and intellectual disability. Among them, Sotos and Weaver syndromes are clinically well defined and due to heterozygous mutations in NSD1 and EZH2, respectively. NSD1 and EZH2 are both histone-modifying enzymes
Constitutional NSD1 and EZH2 mutations cause Sotos and Weaver syndromes respectively, overgrowth syndromes with considerable phenotypic overlap. NSD1 and EZH2 are SET domain-containing histone methyltransferases that play key roles in the regulation of transcription through histone modification and chromatin modeling.
Exact answer: yes