Multi-locus imprinting disturbance (MLID): interim joint statement for clinical and molecular diagnosis.

Background: Imprinting disorders are rare diseases resulting from altered expression of imprinted genes, which exhibit parent-of-origin-specific expression patterns regulated through differential DNA methylation. A subgroup of patients with imprinting disorders have DNA methylation changes at multiple imprinted loci, a condition referred to as multi-locus imprinting disturbance (MLID). MLID is recognised in most but not all imprinting disorders and is also found in individuals with atypical clinical features; the presence of MLID often alters the management or prognosis of the affected person.

Perinatal features of children with Silver-Russell syndrome due to 11p15 loss of methylation.

Background: A diagnosis of Silver-Russell syndrome (SRS), a rare imprinting disorder responsible for foetal growth restriction, is considered for patients presenting at least four criteria of the Netchine-Harbison clinical scoring system (NH-CSS). Certain items of the NH-CSS are not assessable until the age of 2 years. The objective was to determine perinatal characteristics of children with SRS to allow an early diagnosis.

Pubertal origin of growth retardation in inborn errors of protein metabolism: A longitudinal cohort study.

Objectives: Inherited amino-acid metabolism disorders (IAAMDs) require lifelong protein-restricted diet. We aimed to investigate: 1/ whether IAAMDs was associated with growth, pubertal, bone mineral apparent density (BMAD) or body composition impairments; 2/ associations linking height, amino-acid mixture (AAM), plasma amino-acids and IGF1 concentrations.

Design: Retrospective longitudinal study of 213 patients with neonatal-onset urea cycle disorders (UCD,n = 77), organic aciduria (OA,n = 89), maple syrup urine disease (MSUD,n = 34), or tyrosinaemia type 1 (n = 13).