RESUMO
Rubinstein-Taybi syndrome (RSTS) is a developmental disorder characterized by a typical face and distal limbs abnormalities, intellectual disability, and a vast number of other features. Two genes are known to cause RSTS, CREBBP in 60% and EP300 in 8-10% of clinically diagnosed cases. Both paralogs act in chromatin remodeling and encode for transcriptional co-activators interacting with >400 proteins. Up to now 26 individuals with an EP300 mutation have been published. Here, we describe the phenotype and genotype of 42 unpublished RSTS patients carrying EP300 mutations and intragenic deletions and offer an update on another 10 patients. We compare the data to 308 individuals with CREBBP mutations. We demonstrate that EP300 mutations cause a phenotype that typically resembles the classical RSTS phenotype due to CREBBP mutations to a great extent, although most facial signs are less marked with the exception of a low-hanging columella. The limb anomalies are more similar to those in CREBBP mutated individuals except for angulation of thumbs and halluces which is very uncommon in EP300 mutated individuals. The intellectual disability is variable but typically less marked whereas the microcephaly is more common. All types of mutations occur but truncating mutations and small rearrangements are most common (86%). Missense mutations in the HAT domain are associated with a classical RSTS phenotype but otherwise no genotype-phenotype correlation is detected. Pre-eclampsia occurs in 12/52 mothers of EP300 mutated individuals versus in 2/59 mothers of CREBBP mutated individuals, making pregnancy with an EP300 mutated fetus the strongest known predictor for pre-eclampsia. © 2016 Wiley Periodicals, Inc.
Assuntos
Proteína de Ligação a CREB/genética , Proteína p300 Associada a E1A/genética , Pré-Eclâmpsia/genética , Síndrome de Rubinstein-Taybi/genética , Adulto , Montagem e Desmontagem da Cromatina/genética , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto/genética , Pré-Eclâmpsia/fisiopatologia , Gravidez , Síndrome de Rubinstein-Taybi/patologia , Deleção de SequênciaRESUMO
Rubinstein-Taybi syndrome (RSTS) is an autosomal dominant disorder characterized by variable degrees of intellectual disability, an unusual face, distal limb anomalies including broad thumbs and broad halluces, a large group of variable other major and minor anomalies, and decreased somatic growth. The aim of the present study was to construct up-to-date growth charts specific for infants and children with RSTS. We collected retrospective growth data of 92 RSTS individuals of different ancestries. Data were corrected for secular trends and population of origin to the Dutch growth charts of 2009. On average, 17.9 measurements were available per individual. Height, weight and body mass index (BMI) references for males and females were constructed using the lambda, mu, sigma method. RSTS individuals had normal birth weight and length. Mean final heights were 162.6 cm [-2.99 standard deviation score (SDS)] for males and 151.0 cm [-3.01 SDS] for females. BMI SDS compared to the general Dutch population were -0.06 and 1.40 SDS for males and females, respectively. Head circumference SDS compared to the general Dutch population was -1.89 SDS for males and -2.71 SDS for females. This is the first study to publish growth charts using only molecularly proven RSTS individuals. These syndrome-specific growth charts can be used in managing problems related to growth in RSTS individuals.
