KBG syndrome

KBG syndrome is a rare condition characterised by a typical facial dysmorphism, macrodontia of the upper central incisors, skeletal (mainly costovertebral) anomalies and developmental delay. To date, KBG syndrome has been reported in 45 patients. Clinical features observed in more than half of patients that may support the diagnosis are short stature, electroencephalogram (EEG) anomalies (with or without seizures) and abnormal hair implantation. Cutaneous syndactyly, webbed short neck, cryptorchidism, hearing loss, palatal defects, strabismus and congenital heart defects are less common findings. Autosomal dominant transmission has been observed in some families, and it is predominantly the mother, often showing a milder clinical picture, that transmits the disease. The diagnosis is currently based solely on clinical findings as the aetiology is unknown. The final diagnosis is generally achieved after the eruption of upper permanent central incisors at 7–8 years of age when the management of possible congenital anomalies should have been already planned. A full developmental assessment should be done at diagnosis and, if delays are noted, an infant stimulation program should be initiated. Subsequent management and follow-up should include an EEG, complete orthodontic evaluation, skeletal investigation with particular regard to spine curvatures and limb asymmetry, hearing testing and ophthalmologic assessment

One thousand plant transcriptomes and the phylogenomics of green plants

Abstract: Green plants (Viridiplantae) include around 450,000–500,000 species1, 2 of great diversity and have important roles in terrestrial and aquatic ecosystems. Here, as part of the One Thousand Plant Transcriptomes Initiative, we sequenced the vegetative transcriptomes of 1,124 species that span the diversity of plants in a broad sense (Archaeplastida), including green plants (Viridiplantae), glaucophytes (Glaucophyta) and red algae (Rhodophyta). Our analysis provides a robust phylogenomic framework for examining the evolution of green plants. Most inferred species relationships are well supported across multiple species tree and supermatrix analyses, but discordance among plastid and nuclear gene trees at a few important nodes highlights the complexity of plant genome evolution, including polyploidy, periods of rapid speciation, and extinction. Incomplete sorting of ancestral variation, polyploidization and massive expansions of gene families punctuate the evolutionary history of green plants. Notably, we find that large expansions of gene families preceded the origins of green plants, land plants and vascular plants, whereas whole-genome duplications are inferred to have occurred repeatedly throughout the evolution of flowering plants and ferns. The increasing availability of high-quality plant genome sequences and advances in functional genomics are enabling research on genome evolution across the green tree of life

Disruption of TWIST1 translation by 5′ UTR variants in Saethre‐Chotzen syndrome

Saethre-Chotzen syndrome (SCS), one of the most common forms of syndromic craniosynostosis (premature fusion of the cranial sutures), results from haploinsufficiency of TWIST1, caused by deletions of the entire gene or loss-of-function variants within the coding region. To determine whether non-coding variants also contribute to SCS, we screened 14 genetically undiagnosed SCS patients using targeted capture sequencing, and identified novel single nucleotide variants (SNVs) in the 5' untranslated region (UTR) of TWIST1 in two unrelated SCS cases. We show experimentally that these variants, which create translation start sites in the TWIST1 leader sequence, reduce translation from the main open reading frame (mORF). This is the first demonstration that non-coding SNVs of TWIST1 can cause SCS, and highlights the importance of screening the 5' UTR in clinically diagnosed SCS patients without a coding mutation. Similar 5' UTR variants, particularly of haploinsufficient genes, may represent an under-ascertained cause of monogenic disease. This article is protected by copyright. All rights reserved

Disruption of TWIST1 translation by 5′ UTR variants in Saethre‐Chotzen syndrome

Saethre-Chotzen syndrome (SCS), one of the most common forms of syndromic craniosynostosis (premature fusion of the cranial sutures), results from haploinsufficiency of TWIST1, caused by deletions of the entire gene or loss-of-function variants within the coding region. To determine whether non-coding variants also contribute to SCS, we screened 14 genetically undiagnosed SCS patients using targeted capture sequencing, and identified novel single nucleotide variants (SNVs) in the 5' untranslated region (UTR) of TWIST1 in two unrelated SCS cases. We show experimentally that these variants, which create translation start sites in the TWIST1 leader sequence, reduce translation from the main open reading frame (mORF). This is the first demonstration that non-coding SNVs of TWIST1 can cause SCS, and highlights the importance of screening the 5' UTR in clinically diagnosed SCS patients without a coding mutation. Similar 5' UTR variants, particularly of haploinsufficient genes, may represent an under-ascertained cause of monogenic disease. This article is protected by copyright. All rights reserved

Form of autosomal dominant spondyloepiphyseal dysplasia is caused by a glycine to alanine substitution in the COL2A1 gene

Form of autosomal dominant spondyloepiphyseal dysplasia is caused by a glycine to alanine substitution in the COL2A1 gene We report a family with an unusual form of autosomal dominant spondyloepiphyseal dysplasia characterized by infantile-onset disproportionate short stature with relative shortening of the spine, thoracic kyphosis, lumbar lordosis, scoliosis and premature osteoarthritis of the joints especially of the hips. Radiological findings include mild platyspondyly, vertebral end plate irregularity, irregular femoral necks, and dysplasia of the capital femoral epiphyses with flattening and irregularity present from childhood and mild variable epiphyseal dysplasia elsewhere in the skeleton. Intrafamilial variability is observed in the degree of short stature, severity of spinal and hip involvement and the age of onset of symptoms and complications. We demonstrate that this dysplasia is due to a glycine to alanine substitution in the COL2A1 gene (p.Gly862Ala), thereby expanding the phenotypic spectrum of dysplasias associated with defects in type II collagen