Aortic root dilation in apparent Lujan-Fryns syndrome

MED12 Regulates Smooth Muscle Cell Functions and Participates in the Development of Aortic Dissection

Aortic dissection (AD) is a life-threatening disease with high morbidity and mortality, and effective pharmacotherapeutic remedies for it are lacking. Therefore, AD’s molecular pathogenesis and etiology must be elucidated. The aim of this study was to investigate the possible mechanism of mediator complex subunit 12 (human: MED12, mouse: Med12)involvement in AD. Firstly, we examined the expression of MED12 protein (human: MED12, mouse: Med12) in the aortic tissues of AD patients and AD mice. Subsequently, Med12 gene silencing was accomplished with RNA interference (siRNA). The effects of Med12 on AD and the possible biological mechanisms were investigated based on the proliferation, senescence, phenotypic transformation, and its involved signal pathway of mouse aortic smooth muscle cells (MOVAS), s. The results show that the expression of MED12 in the aortae of AD patients and AD mice was decreased. Moreover, the downregulation of Med12 inhibited the proliferation of MOVAS and promoted senescence. Further research found that Med12, as an inhibitor of the TGFβ1 signaling pathway, reduced the expression of Med12 and enhanced the activity of the TGFβ1 nonclassical signaling pathway, while TGFβ1 inhibited the phenotype transformation and proliferation of MOVAS by inhibiting Med12 synthesis. In conclusion, Med12 affected the phenotype, proliferation, and senescence of MOVAS through the TGFβ signaling pathway. This study provides a potential new target for the prevention and treatment of AD.

Role of Epigenetics in Cardiac Development and Congenital Diseases

The heart is the first organ to be functional in the fetus. Heart formation is a complex morphogenetic process regulated by both genetic and epigenetic mechanisms. Congenital heart diseases (CHD) are the most prominent congenital diseases. Genetics is not sufficient to explain these diseases or the impact of them on patients. Epigenetics is more and more emerging as a basis for cardiac malformations. This review brings the essential knowledge on cardiac biology of development. It further provides a broad background on epigenetics with a focus on three-dimensional conformation of chromatin. Then, we summarize the current knowledge of the impact of epigenetics on cardiac cell fate decision. We further provide an update on the epigenetic anomalies in the genesis of CHD.

Lujan-Fryns Syndrome (LFS): A Unique Combination of Hypernasality, Marfanoid Body Habitus, and Neuropsychiatric Issues, Presenting as Acute-Onset Dysphagia

BACKGROUND

Lujan–Fryns syndrome (LFS) is an extremely rare, X-linked disorder, for which the full clinical spectrum is still unknown. Usually, it presents with neuropsychiatric problems such as learning disabilities and behavioral issues in a typical combination with marfanoid features. Often, there is a positive family history for the disorder. However, sporadic cases have also been reported in males. More interestingly, there is no case of LFS presenting with acute-onset dysphagia in the English language medical literature.

CASE PRESENTATION

A 17-year-old Pakistani mentally normal school boy was admitted for the workup of acute-onset dysphagia, hypernasal speech, and nasal regurgitation of liquids. He had no neuropsychiatric issues, and his family history was unremarkable. An obvious nasal twang, facial dysmorphism, and marfanoid body habitus were found on examination. The genetic tests revealed a pathogenic missense mutation in the MED12 gene on his X-chromosome.

CONCLUSION

LFS can present as acute-onset dysphagia and in the absence of any neuropsychiatric issues or positive family history of the syndrome.

Systematic molecular and cytogenetic screening of 100 patients with marfanoid syndromes and intellectual disability

The association of marfanoid habitus (MH) and intellectual disability (ID) has been reported in the literature, with overlapping presentations and genetic heterogeneity. A hundred patients (71 males and 29 females) with a MH and ID were recruited. Custom-designed 244K array-CGH (Agilent®; Agilent Technologies Inc., Santa Clara, CA) and MED12, ZDHHC9, UPF3B, FBN1, TGFBR1 and TGFBR2 sequencing analyses were performed. Eighty patients could be classified as isolated MH and ID: 12 chromosomal imbalances, 1 FBN1 mutation and 1 possibly pathogenic MED12 mutation were found (17%). Twenty patients could be classified as ID with other extra-skeletal features of the Marfan syndrome (MFS) spectrum: 4 pathogenic FBN1 mutations and 4 chromosomal imbalances were found (2 patients with both FBN1 mutation and chromosomal rearrangement) (29%). These results suggest either that there are more loci with genes yet to be discovered or that MH can also be a relatively non-specific feature of patients with ID. The search for aortic complications is mandatory even if MH is associated with ID since FBN1 mutations or rearrangements were found in some patients. The excess of males is in favour of the involvement of other X-linked genes. Although it was impossible to make a diagnosis in 80% of patients, these results will improve genetic counselling in families.

Characterization of a new X-linked mental retardation syndrome with microcephaly, cortical malformation, and thin habitus

X-linked mental retardation (XLMR) affects 1-2/1,000 males and accounts for approximately 10% of all mental retardation (MR). We have ascertained a syndromic form of XLMR segregating within a five-generation family with seven affected males. Prominent characteristics include mild to severe MR, cortical malformation, microcephaly, seizures, thin build with distinct facial features including a long and thin face, epicanthic folds, almond-shaped eyes, upslanting palpebral fissures and micrognathia and behavioral problems. Carrier females have normal physical appearance and intelligence. This combination of features is unreported and distinct from Lujan-Fryns syndrome, Snyder-Robinson syndrome, and zinc finger DHHC domain-containing 9-associated MR. We propose the name of this new syndrome to be CK syndrome.

Lujan-Fryns syndrome (mental retardation, X-linked, marfanoid habitus)

The Lujan-Fryns syndrome or X-linked mental retardation with marfanoid habitus syndrome is a syndromal X-linked form of mental retardation, affecting predominantly males. The prevalence is not known for the general population. The syndrome is associated with mild to moderate mental retardation, distinct facial dysmorphism (long narrow face, maxillary hypoplasia, small mandible and prominent forehead), tall marfanoid stature and long slender extremities, and behavioural problems. The genetic defect is not known. The diagnosis is based on the presence of the clinical manifestations. Genetic counselling is according to X-linked recessive inheritance. Prenatal testing is not possible. There is no specific treatment for this condition. Patients need special education and psychological follow-up, and attention should be given to diagnose early psychiatric disorders.

Eating disorder in a patient with phenotypical features of Lujan-Fryns syndrome

We report a young patient with phenotypic, cognitive and behavioural features consistent with a diagnosis of Lujan-Fryns syndrome. He exhibited a severe eating disorder with food refusal and psychogenic loss of appetite, which led to a serious state of malnutrition. Behavioural difficulties including shyness, hyperactivity and emotional instability are present in almost 80% of the described patients with Lujan-Fryns syndrome but eating disorders have not been previously reported in this condition. A review of the behavioural problems in Lujan-Fryns syndrome and an approach to their management is discussed.

Psychopathology in the Lujan–Fryns syndrome: Report of two patients and review

We report on two new patients, the propositus and his maternal uncle, with Lujan-Fryns syndrome (LFS). One presented with mild mental retardation and both patient had Marfanoid habitus and similar craniofacial anomalies (they had a long and narrow face, small mandible, high-arched palate, and hypernasal voice) as previously reported by Lujan et al. in 1984 and Fryns and Buttiens in 1987. One of our patients had agenesis of the corpus callosum as described by Lujan. The second patient had an ascending aortic aneurysm like the patient described by Wittine et al. 1999. Both patients showed similar behavior and psychiatric disorders. In addition, we reviewed the literature for the presence of psychopathology in LFS. After studying the 32 published cases and the 2 described in this article, we found that more than 90% of the patients present with some type of psychopathology, the most frequent being an autistic-like disorder. In our opinion, the agenesis of the corpus callosum (complete or partial) and ascending aorta aneurysm are manifestations of LFS, and thus brain MRI and echocardiogram should be part of the routine evaluation. Additionally, the high prevalence of psychopathological alterations in these patients suggests the need for psychiatric evaluation at the time of diagnosis.

Terminal deletion of chromosome 5p in a patient with phenotypical features of Lujan-Fryns syndrome

We report a young man with phenotypical features suggestive of Lujan-Fryns syndrome and behaviour of an autistic spectrum disorder, who has a subtle terminal deletion of the short arm of chromosome 5. Individuals reported previously with a similar chromosomal abnormality have had developmental delay and a 'breathy, raspy' voice. It may be appropriate to consider screening patients with a phenotype suggestive of Lujan-Fryns syndrome by fluorescence in situ hybridisation (FISH) using a probe for the subtelomeric region of the short arm of chromosome 5.

Preserved neurobehavioral abilities in Lujan-Fryns syndrome

We present a patient with all the physical characteristics of Lujan-Fryns syndrome, including Marfanoid habitus, mild general hypotonia, hypernasal voice, normal testicular size, and distinct craniofacial anomalies. Despite the presence of impaired mental abilities in many areas, this young man showed intact concrete problem-solving skills under structured, interactive conditions. In addition, he did not demonstrate any of the psychiatric features that have often been reported with this syndrome. We conclude that Lujan-Fryns syndrome can be associated with partial preservation of neurobehavioral abilities.