MED12 missense mutation in a three-generation family. Clinical characterization of MED12-related disorders and literature review.

Mutations in MED12 gene have been described in association with syndromic and non-syndromic X-linked intellectual disability (XLID). Up to date at least three distinct XLID syndromes have been described: FG syndrome, Lujan-Fryns syndrome (LS) and Ohdo syndrome (OSMKB). In the last years, thanks to the massive use of next generation sequencing techniques (NGS) it has been possible to discover at least 16 others MED12 mutations and to expand the phenotype of MED12-related disorders. Here we report three subjects from a large non-consanguineous family presenting with a mild to severe ID, important speech delay, behavior problems, dysmorphic facial features and hearing loss. NGS allows us to detect the MED12 missense variant c.3883C > T (p.(Arg1295Cys)) carried by the three patients. This variant has been reported in 2016 by Hu et al. in one family from a big cohort of XLID families. This clinical report contributes to expanding the phenotype associated with MED12-mutations.

Premature ovarian insufficiency as a variable feature of blepharophimosis, ptosis, and epicanthus inversus syndrome associated with c.223C > T p.(Leu75Phe) FOXL2 mutation: a case report.

BACKGROUND: FOXL2 gene mutations cause blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) and may be associated with premature ovarian insufficiency (POI). Two types of BPES were described in the literature. BPES type 2 is a simple association of inherited developmental defects of the eyelid area, while in type 1 female patients additionally suffer from POI. The following case study is the first report of endocrine impairments typical for menopausal transition in young female with NG_012454.1:g.138665342G > A, c.223C > T p.(Leu75Phe), mutation in FOXL2 gene. This mutation has been reported in the literature before, however until now, it was never linked to BPES type 1. CASE PRESENTATION: An 18-year-old nulliparous woman suspected of secondary amenorrhea was referred to our Endocrinology Outpatient Clinic. Blood tests revealed decreased levels of AMH (anti-Mullerian hormone) and increased levels of gonadotropins, suggesting menopausal transition. Her past medical history was remarkable for several ophthalmic defects that has required surgical interventions. BPES syndrome had not been suspected before, although the patient had reported a similar phenotype occurring in her father, sister and half-sister. Venous blood samples were collected from the female proband and from her three family members. Whole-exome sequencing and deep amplicon sequencing were performed. A potential pathogenic variant in the FOXL2 gene was revealed. Namely, the c.223C > T p.(Leu75Phe) missense variant was detected. CONCLUSIONS: The authors found mutations, c.223C > T p.(Leu75Phe) in the FOXL2 gene in a young woman with hormonal disorders suggesting menopausal transition. These results indicate that the possibility of different phenotypes should be considered in patients with a similar genetic mutation.

Clinical characterization and identification of five novel FOXL2 pathogenic variants in a cohort of 12 Mexican subjects with the syndrome of blepharophimosis-ptosis-epicanthus inversus.

Blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) is an autosomal dominant entity characterized by eyelid malformations and caused by mutations in the forkhead box L2 (FOXL2) gene. Clinical and genetic analyses of large cohorts of BPES patients from different ethnic origins are important for a better characterization of FOXL2 mutational landscape. The purpose of this study is to describe the phenotypic features and the causal FOXL2 variants in a Mexican cohort of BPES patients. A total of 12 individuals with typical facial findings were included. Clinical evaluation included palpebral measurements and levator function assessment. The complete coding sequence of FOXL2 was amplified by PCR and subsequently analyzed by Sanger sequencing. A total of 11 distinct FOXL2 pathogenic variants were identified in our cohort (molecular diagnostic rate of 92%), including 5 novel mutations. Our results broaden the BPES-related mutational spectrum and supports considerable FOXL2 allelic heterogeneity in our population.

Novel truncating variants expand the phenotypic spectrum of KAT6B-related disorders.

Say-Barber-Biesecker-Young-Simpson syndrome (SBBYSS) and Genitopatellar syndrome (GTPTS) are very rare conditions caused by KAT6B truncating variants. Because of both syndromes often share common features the associated phenotypes are usually grouped under the term "KAT6B-related disorders." However, particular signs of each syndrome have been reported and their appearance seems to be dependent on where the KAT6B variant is located. Thus, whereas truncating variants associated with SBBYSS have their highest density in the distal part of exon 18, those resulting in GTPTS are distributed between the end of exon 17 and beginning of exon 18. Here, we reported two de novo heterozygous KAT6B truncating variants. The first variant (c.5802delA; p.A1935Pfs*16), identified in a boy with SSBYSS phenotype, resulting in the most distal KAT6B truncating variant reported up-to-date in the scientific literature. The second variant (c.3152delG; p.S1051Tfs*63), located in a region hitherto defined as specific of SBBYSS, seems to cause an overlapping SBBYSS/GTPTS phenotype. The clinical and genetic characterization of these patients could contribute to the understanding of the KAT6B-related disorders.

A novel truncating variant within exon 7 of KAT6B associated with features of both Say-Barber-Bieseker-Young-Simpson syndrome and genitopatellar syndrome: Further evidence of a continuum in the clinical spectrum of KAT6B-related disorders.

KAT6B sequence variants have been identified in both patients with the Say-Barber-Biesecker-Young-Simpson syndrome (SBBYSS) and in the genitopatellar syndrome (GPS). In SBBYSS, they were reported to affect mostly exons 16-18 of KAT6B, and the predicted mechanism of pathogenesis was haploinsufficiency or a partial loss of protein function. Truncating variants in KAT6B leading to GPS appear to cluster within the proximal portion of exon 18, associated with a dominant-negative effect of the mutated protein, most likely. Although SBBYSS and GPS have been initially considered allelic disorders with distinctive genetic and clinical features, there is evidence that they represent two ends of a spectrum of conditions referable as KAT6B-related disorders. We detected a de novo truncating variant within exon 7 of KAT6B in a 8-year-old female who presented with mild intellectual disability, facial dysmorphisms highly consistent with SBBYSS, and skeletal anomalies including exostosis, that are usually considered component manifestations of GPS. Following the clinical diagnosis driven by the striking facial phenotype, we analyzed the KAT6B gene by NGS techniques. The present report highlights the pivotal role of clinical genetics in avoiding clear-cut genotype-phenotype categories in syndromic forms of intellectual disability. In addition, it further supports the evidence that a continuum exists within the clinical spectrum of KAT6B-associated disorders.

Further evidence that a blepharophimosis syndrome phenotype is associated with a specific class of mutation in the ADNP gene.

Heterozygous truncating mutations in ADNP are associated with a syndromic form of intellectual disability known as Helsmoortel-van der Aa syndrome. Among 17 previously reported patients with Helsmoortel-van der Aa syndrome, one patient exhibited blepharophimosis. Whether blepharophimosis represents a phenotypic expression of the ADNP mutation spectrum or a chance association remains unclear. Herein, we report another patient with a de novo truncating mutation in ADNP who exhibited a combination of blepharophimosis and epicanthal folds. In our retrospective re-evaluation of six originally reported patients whose facial photographs were available, at least one patient indeed had blepharophimosis and epicanthal folds. Furthermore, all three patients with blepharophimosis and epicanthal folds, including the presently reported patient, had truncating mutations at the same specific portion of the protein, that is the bipartite nuclear localization signal. We suggest that this specific class of ADNP mutation is likely associated with a blepharophimosis syndrome phenotype. From a clinical standpoint, a differential diagnosis of patients with blepharophimosis should include ADNP mutations in addition to blepharophimosis ptosis epicanthus inversus syndrome, especially when intellectual disability is present.

Characterization of endocrine features and genotype-phenotypes correlations in blepharophimosis-ptosis-epicanthus inversus syndrome type 1.

OBJECTIVE: Blepharophimosis syndrome (BPES) is an autosomal dominant genetic condition resulting from heterozygous mutations in the FOXL2 gene and clinically characterized by an eyelid malformation associated (type I) or not (type II) with premature ovarian failure. The distinction between the two forms is critical for female patients, as it may allow to predict fertility and to plan an appropriate therapy. Identifying an underlying causative mutation is not always predictive of the clinical type of BPES since genotype-phenotype correlations are not yet fully delineated. Here, we describe the clinical and hormonal phenotypes of three female patients with BPES type 1 from two novel families, correlate their phenotypes with identified mutations, and investigate the effects of hormone replacement therapy (HRT). METHODS: Clinical, biochemical, and genetic evaluation were undertaken in all the patients and genotype-phenotype correlation was analyzed. The effects of substitutive hormonal therapy on secondary sexual characteristics development and induction of menarche were evaluated. RESULTS: All patients presented with primary amenorrhea or other signs of ovarian dysfunction. Two distinct mutations, a missense p.H104R change and an in-frame p.A222_A231dup10 duplication in the FOXL2 gene were identified. Observed phenotypes were not in accordance with the prediction based on the current genotype-phenotype correlations. HRT significantly improved secondary sexual characteristics development, as well as the induction of menarche. CONCLUSIONS: This study highlights the importance of early recognition of BPES and emphasizes the need of personalized therapy and follow-up in female patients carrying distinct FOXL2 mutations.

Facial abnormalities in Nablus mask-like facial syndrome: multidetector computed tomography findings.

Nablus mask-like facial syndrome (NMLFS) is a rare microdeletion syndrome characterized by a mask-like facial appearance. NMLFS has been reported in only 6 patients and has a recognizable facial appearance, along with other clinical features. The first case of NMLFS has been described by Teebi in 2000, in a 4-year-old Palestinian boy. Three years later, Salpietro et al reported a second example of NMLFS in a 21-month-old girl. The same patient recently came to our hospital to undergo a computed tomography (CT) study to evaluate the degree of development of the zygomatic-maxillary region for orthodontic treatment and orthognathic surgery. To the best of our knowledge, no reports have previously illustrated the maxillofacial CT findings of NMLFS in the radiologic data. We report the multidetector CT (MDCT) facial characteristics/abnormalities of this syndrome, emphasizing the usefulness of multiplanar reformations (MPRs) in preoperative planning.

Clinical and neurocognitive characterization of a family with a novel MED12 gene frameshift mutation.

FG syndrome, Lujan syndrome, and Ohdo syndrome, the Maat-Kievit-Brunner type, have been described as distinct syndromes with overlapping non-specific features and different missense mutations of the MED12 gene have been reported in all of them. We report a family including 10 males and 1 female affected with profound non-specific intellectual disability (ID) which was linked to a 30-cM region extending from Xp11.21 (ALAS2) to Xq22.3 (COL4A5). Parallel sequencing of all X-chromosome exons identified a frameshift mutation (c.5898dupC) of MED12. Mutated mRNA was not affected by non-sense mediated RNA decay and induced an additional abnormal isoform due to activation of cryptic splice-sites in exon 41. Dysmorphic features common to most affected males were long narrow face, high forehead, flat malar area, high nasal bridge, and short philtrum. Language was absent or very limited. Most patients had a friendly personality. Cognitive impairment, varying from borderline to profound ID was similarly observed in seven heterozygous females. There was no correlation between cognitive function and X-chromosome inactivation profiles in blood cells. The severe degree of ID in male patients, as well as variable cognitive impairment in heterozygous females suggests that the duplication observed in the present family may have a more severe effect on MED12 function than missense mutations. In a cognitively impaired male from this family, who also presented with tall stature and dysmorphism and did not have the MED12 mutation, a 600-kb duplication at 17p13.3 including the YWHAE gene, was found in a mosaic state.

Wakayama Symposium: Notch-FoxL2-α-SMA axis in eyelid levator muscle development and congenital blepharophimosis.

This review summarizes our recent findings regarding the Notch signaling pathway in regulating normal eyelid morphogenesis and its role in the pathogenesis of human congenital blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES). We used genetic and molecular biological approaches to investigate the mechanism by which Notch1 activation controls expression of FoxL2, which in turn activates smooth muscle actin gene expression in periocular mesenchyma to control eyelid levator smooth muscle formation.

The combination of polyalanine expansion mutation and a novel missense substitution in transcription factor FOXL2 leads to different ovarian phenotypes in blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) patients.

STUDY QUESTION: What are the implications of multiple alterations of the forkhead box L2 (FOXL2) gene in blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) patients? SUMMARY ANSWER: A multi-mutation of FOXL2, consisting of the expansion of the polyalanine tract from 14 to 24 residues (FOXL2-Ala24), an novel Y186C substitution from c.557A>G, and a synonymous variant (c.505G>A), had a cumulative effect on ovarian phenotypes in BPES patients. WHAT IS KNOWN ALREADY: Mutations in FOXL2, a gene encoding a forkhead transcription factor cause BPES. Overall, the expansion of the polyalanine tract of FOXL2 from 14 to 24 residues (FOXL2-Ala24) accounts for 30% of intragenic mutations. STUDY DESIGN, SIZE, DURATION: In this study, patients from seven BPES families and six sporadic cases were included. PARTICIPANTS/MATERIALS, SETTING, METHODS: We conducted an extensive clinical, hormonal and functional study in 20 patients carrying the expansion of the polyalanine tract of FOXL2 associated with BPES. A multi-mutation of FOXL2 was detected in one BPES family that showed more severe BPES symptoms. Subcellular localization and transactivation studies were performed for the constructs of FOXL2-Ala24, Y186C and FOXL2-Ala24-Y186C. MAIN RESULTS: We described the first multi-mutation of FOXL2 (c. [672_701dup30; 557A>G]) that leads to the polyalanine expansion of +10 residues (FOXL2-Ala24) combined with an Y186C substitution and a synonymous variant in a Chinese BPES family. This multi-mutation genotype was associated with more serious BPES clinical manifestations and the development of esotropia in the right eye. In in vitro studies, the multi-mutation affected the function of FOKL2 on the StAR promoter and DK3, and induced more aggressive aggregation and mislocalization of FOXL2 protein. The synonymous variant, while not affecting amino acid coding, causes a change in the RNA stem-loop structure. LIMITATIONS, REASONS FOR CAUTION: The multi-mutation of FOXL2 was detected in one BPES family and it needs to be validated further by more BPES subjects. WIDER IMPLICATIONS OF THE FINDINGS: The results of our study contribute new insights into the research field of BPES caused by the multi-mutation of FOXL2. STUDY FUNDING/COMPETING INTERESTS: This study was supported by Shanghai Leading Academic Discipline Project (Grant number S30205) and Shanghai Jiao Tong University School of Medicine Doctor Innovation Fund (Grant number 201131). The authors have no competing interests to declare.

Discovery of novel protein partners of the transcription factor FOXL2 provides insights into its physiopathological roles.

FOXL2 transcription factor is responsible for the Blepharophimosis Ptosis Epicantus inversus Syndrome (BPES), a genetic disease involving craniofacial malformations often associated with ovarian failure. Recently, a somatic FOXL2 mutation (p.C134W) has been reported in >95% of adult-type granulosa cell tumors. Here, we have identified 10 novel FOXL2 partners by yeast-two-hybrid screening and co-immunoprecipitation. Most BPES-inducing mutated FOXL2 proteins display aggregation in cultured cells. Here, we show that two of the partners (NR2C1 and GMEB1) can be sequestered in such aggregates. This co-aggregation can contribute to the pathogenesis of FOXL2 mutations. We have also measured the effects of FOXL2 interactants on the transcriptional regulation of a series of target promoters. Some of the partners (CXXC4, CXXC5, BANF1) were able to repress FOXL2 activity indistinctively of the promoter. Interestingly, CREM-τ2α, which acted as a repressor on most promoters, increased wild-type (WT) FOXL2 activity on two promoters (PTGS2 and CYP19A1), but was unable to increase the activity of the oncogenic mutant p.C134W. Conversely, GMEB1, which also acted as a repressor on most promoters and increased WT FOXL2 activity on the Per2 promoter, increased to a greater extent the activity of the p.C134W variant. Interestingly, partners with intrinsic pro-apoptotic effect were able to increase apoptosis induction by WT FOXL2, but not by the p.C134W mutant, whereas partners with an anti-apoptotic effect decreased apoptosis induction by both FOXL2 versions. Altogether, these results suggest that the p.C134W mutated form fails to integrate signals through protein-protein interactions to regulate target promoter subsets and in particular to induce cell death.

Single stage surgery for Blepharophimosis syndrome.

PURPOSE: The purpose of this study was to report the functional and cosmetic outcome of single stage surgical procedure for correction of the classic components of Blepharophimosis syndrome. MATERIALS AND METHODS: We report a retrospective case file review of 11 patients with Blepharophimosis syndrome operated between July 2004 and April 2008. Each patient had undergone the correction of epicanthus inversus, telecanthus, palpebral phimosis, and bilateral ptosis as a single-stage surgical procedure. Patients were examined and photographed before and after surgery. The mean follow-up was 3 years (range 2-6 years). RESULTS: A total of 11 patients (8 males, 3 females) with a mean age of 9 years (range 6--22 years) were reviewed. The surgical outcome was assessed both functionally and cosmetically. The mean preoperative visual acuity was 0.729 ± 0.316 SD and the mean postoperative visual acuity was 0.856 ± 0.277 SD (P <0.0428). There was a statistically significant decrease of astigmatism following ptosis correction (P<0.05), improvement of telecanthus (P<0.0001) in terms of IICD (inner intercanthal distance), and HPFL (horizontal palpebral fissure length) (P=0.019) along with improvement of the superior visual field. The mean preoperative and postoperative IICD was 3±0.33 SD and 2.418 ± 0.189 SD, respectively. There was also a significant postoperative improvement of ptosis (P< 0.01), as measured by IPFH (vertical interpalpebral fissure height). All the patients had a stable functional and cosmetic result after a mean follow-up period of 3 years. CONCLUSION: Single-stage surgical correction of the classic anomalies of Blepharophimosis syndrome provides stable and successful long-term results.

Severe acute respiratory failure secondary to acute fibrinous and organizing pneumonia requiring mechanical ventilation: a case report and literature review.

A 27-year-old woman was admitted to our ICU with acute hypoxemic respiratory failure and criteria for ARDS. Despite an F(IO(2)) of 1.0 and a lung protective strategy, the patient died on day 15 without any improvement. The relatives gave consent for post-mortem analysis. The histopathologic study of the lung showed findings typical of an acute fibrinous and organizing pneumonia. Apropos of this case we performed a PubMed search. We found 13 articles, including a total of 29 patients. Acute fibrinous and organizing pneumonia is an unusual cause of acute lung injury. The diagnostic criterion is histopathologic. There is little information regarding the pathophysiology of this illness. Important questions remain regarding this disease, including predisposing factors and management. Patients who require mechanical ventilation have poor outcomes.

Insights into levator muscle dysfunction in a cohort of patients with molecularly confirmed blepharophimosis-ptosis-epicanthus inversus syndrome using high-resolution imaging, anatomic examination, and histopathologic examination.

OBJECTIVE: To study the basis of defective levator palpebrae superioris (LPS) function in blepharophimosis-ptosis-epicanthus inversus syndrome (BPES), an autosomal dominant eyelid malformation sometimes associated with ovarian dysfunction. METHODS: Eight patients with molecularly proved BPES underwent high-resolution surface-coil 3-T magnetic resonance imaging before surgical intervention. The features of LPS muscle and adjoining connective tissue were compared with an age-matched control subject. During LPS resection for ptosis repair, detailed anatomic examination of the LPS was performed. Histopathologic characteristics were compared with normal control samples from a cadaver and a patient with simple severe congenital ptosis. RESULTS: The most striking feature shown on magnetic resonance imaging was the thin, long anterior part of the LPS. During the operation, this consisted of a disorganized, thin, long aponeurosis. However, in the posterior part of the LPS, there was an organized thick structure suggestive of a muscle belly. Histopathologic examination revealed posteriorly well-formed striated muscle fibers in all patients with BPES but not in the control sample from the patient with simple severe congenital ptosis. These striated muscle fibers were comparable to those of the normal control tissue but were more intermixed with collagenous tissue and little fatty degeneration. CONCLUSIONS: The presence of striated muscle fibers in LPS of patients with BPES contrasts with the fatty degeneration in patients with simple severe congenital ptosis. To our knowledge, this is the first study providing novel insights into the pathogenesis of the eyelid malformation in BPES through extensive imaging, anatomic study, and histopathologic testing in a unique cohort of patients with molecularly proved BPES.

Congenital hydrocephalus in clinical practice: a genetic diagnostic approach.

Congenital hydrocephalus is a common and often disabling disorder. The etiology is very heterogeneous. Little is known about the genetic causes of congenital hydrocephalus. A retrospective survey was performed including patients with primary congenital hydrocephalus referred to the Department of Clinical Genetics between 1985 and 2010 by perinatologists, (child) neurologists or pediatricians. Patients with hydrocephalus secondary to other pathology were excluded from this survey. We classified patients with primary congenital hydrocephalus into two main groups: non-syndromic hydrocephalus (NSH) and syndromic hydrocephalus (SH). Seventy-five individuals met the inclusion criteria, comprising 36% (27/75) NSH and 64% (48/75) SH. In 11% (8/75) hydrocephalus was familial. The cause of hydrocephalus was unknown in 81% (61/75), including all patients with NSH. The male-female ratio in this subgroup was 2.6:1, indicating an X-linked factor other than the L1CAM gene. In the group of SH patients, 29% (14/48) had a known cause of hydrocephalus including chromosomal abnormalities, L1 syndrome, Marden-Walker syndrome, Walker-Warburg syndrome and hemifacial microsomia. We performed this survey in order to evaluate current knowledge on the genetic etiology of primary congenital hydrocephalus and to identify new candidate genes or regulatory pathways for congenital hydrocephalus. Recommendations were made concerning the evaluation and genetic workup of patients with primary congenital hydrocephalus. We conclude that further molecular and functional analysis is needed to identify new genetic forms of congenital hydrocephalus.

Increased levator muscle function by supramaximal resection in patients with blepharophimosis-ptosis-epicanthus inversus syndrome.

OBJECTIVE: To study the efficacy and clinical and anatomical results of supramaximal levator resection in patients with blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) with severe congenital ptosis with poor levator function (LF). METHODS: Eleven patients with molecularly proven BPES underwent supramaximal levator resection. Palpebral fissure height and LF were measured preoperatively and postoperatively. RESULTS: All patients showed an excellent reduction in ptosis with a single intervention resulting in a clear visual axis. Palpebral fissure height improved from mean (SD) 3.3 (0.7) mm preoperatively to 7.1 (0.9) mm postoperatively (P value <.001). Four patients underwent additional surgery because of cosmetic issues with eyelid height asymmetry. All patients showed a marked, consistent, and lasting improvement in LF, going from mean (SD) 1.9 (0.9) mm preoperatively to 7.4 (1.1) mm postoperatively (P value <.001). This improvement could be attributed to the presence of a very long and thin tendon, as well as a striated muscle belly. This elongated aponeurosis inhibits the levator muscle from having sufficient impact on the vertical eyelid excursion. CONCLUSIONS: We demonstrated that supramaximal levator resection performed in patients with BPES not only results in good cosmetic appearance in terms of ptosis reduction in the majority of cases but also in a significant increase of the levator palpebrae superioris function. An anatomical substrate was found to explain these findings. To our knowledge, this is the first study to provide evidence of a marked increase in LF in BPES due to resection of the elongated tendon with reinsertion of the muscle belly.