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3D analysis of facial morphology has delineated facial phenotypes in many medical conditions and detected fine grained differences between typical and atypical patients to inform genotype-phenotype studies. Next-generation sequencing techniques have enabled extremely detailed genotype-phenotype correlative analysis. Such comparisons typically employ, control groups matched for age, sex and ethnicity and the distinction-between ethnic categories in genotype-phenotype studies has been widely debated. The phylogenetic tree based on genetic polymorphism studies divides the world population into nine subpopulations. Here we show statistically significant face shape differences between two European Caucasian populations of close phylogenetic and geographic proximity from the UK and The Netherlands. The average face shape differences between the Dutch and UK cohorts were visualised in dynamic morphs and signature heat maps, and quantified for their statistical significance using both conventional anthropometry and state of the art dense surface modelling techniques. Our results demonstrate significant differences between Dutch and UK face shape. Other studies have shown that genetic variants influence normal facial variation. Thus, face shape difference between populations could reflect underlying genetic difference. This should be taken into account in genotype-phenotype studies and we recommend that in those studies reference groups be established in the same population as the individuals who form the subject of the study

Mutations in the RECQL4 gene can lead to three clinical phenotypes with overlapping features. All these syndromes, Rothmund-Thomson (RTS), RAPADILINO and Baller-Gerold (BGS), are characterized by growth retardation and radial defects, but RAPADILINO syndrome lacks the main dermal manifestation, poikiloderma that is a hallmark feature in both RTS and BGS. It has been previously shown that RTS patients with RECQL4 mutations are at increased risk of osteosarcoma, but the precise incidence of cancer in RAPADILINO and BGS has not been determined. Here, we report that RAPADILINO patients identified as carriers of the c.1390+2delT mutation (p.Ala420_Ala463del) are at increased risk to develop lymphoma or osteosarcoma (6 out of 15 patients). We also summarize all the published RECQL4 mutations and their associated cancer cases and provide an update of 14 novel RECQL4 mutations with accompanying clinical data.

Cornelia de Lange Syndrome (CdLS) is a multiple congenital anomaly syndrome characterized by a distinctive facial appearance, malformations of the upper limbs, and delay in growth and development. Mutations in NIPBL are associated with CdLS in 27-56% of cases and have been reported as point mutations, small insertions and deletions in coding regions, regulatory regions and at splice junctions. All previous studies used PCR-based exon-scanning methodologies that do not allow detection of large genomic rearrangements. We studied the relative copy number of NIPBL exons in a series of 50 CdLS probands, negative for NIPBL mutations, by multiplex ligation-dependent probe amplification (MLPA). In a single patient, we found a 5.2 kb deletion encompassing exons 41-42 of NIPBL. Our studies indicate that large NIPBL rearrangements do occur in CdLS but are likely to be infrequent events.

We report on a four-generation family with localized subepidermal telangiectasias following Blaschko's lines (angioma serpiginosum). The vascular streaks are present at birth and progress slowly thereafter. In several family members papillomatosis of the entire oesophagus was found to be part of the condition. Mild nail and hair dystrophy added to the resemblance of Goltz-Gorlin syndrome (focal dermal hypoplasia), suggesting that the present condition could be a mild variant. All affected family members are females, there is no increased miscarriage rate, and X-inactivation in affected females is highly skewed, compatible with X-linked dominant inheritance with very early in utero lethality in males. In the family, 11 informative meioses were available to study the segregation of X-chromosome markers. Significant linkage (LOD score 3.31) was found to a region flanked by markers DXS8026 and DXS106 (44-67 Mb from Xpter) that includes the centromere.

In this review a short overview of pertinent clinical and molecular data of the Rubinstein-Taybi syndrome are provided. A diagnostic decision algorithm, and major issues that should be considered in the management of patients are discussed. Suggestions for further research are given.

We describe a newborn with complete absence of ossification of the ribs, extreme micrognathia, absence of external ear canals and the inner ears, and diminished mobility in the upper extremities. It is suggested that this represents an unusually severe expression of the cerebro-costo-mandibular syndrome. Some developmental genes that may have played a role in the pathogenesis are briefly reviewed.

Programmed cell death is a physiological process in mammalian development by which specific types of cells are eliminated, and, hence, is of fundamental importance in normal human embryogenesis. A patient is described with multiple congenital anomalies that may be explained by a disturbance of programmed cell death. Anomalies included macrocephaly, hypoplastic lacrimal ducts, narrow external ear canals, pharyngeal mucous membrane fold, unilateral cryptorchidism, cord-like vasa deferentia, and complete cutaneous syndactyly of the hands and feet.

Correction to: European Journal of Human Genetics advance online publication, 15 January 2014; doi:10.1038/ejhg.2013.288 After the above article had been published online, it was brought to the authors’ attention that Figure 1 contained an image for which the patient had not given his consent for publication.