Clinical description, molecular delineation and genotype-phenotype correlation in 340 patients with KBG syndrome: addition of 67 new patients.

BACKGROUND: KBG syndrome is a highly variable neurodevelopmental disorder and clinical diagnostic criteria have changed as new patients have been reported. Both loss-of-function sequence variants and large deletions (copy number variations, CNVs) involving ANKRD11 cause KBG syndrome, but no genotype-phenotype correlation has been reported. METHODS: 67 patients with KBG syndrome were assessed using a custom phenotypical questionnaire. Manifestations present in >50% of the patients and a 'phenotypical score' were used to perform a genotype-phenotype correlation in 340 patients from our cohort and the literature. RESULTS: Neurodevelopmental delay, macrodontia, triangular face, characteristic ears, nose and eyebrows were the most prevalentf (eatures. 82.8% of the patients had at least one of seven main comorbidities: hearing loss and/or otitis media, visual problems, cryptorchidism, cardiopathy, feeding difficulties and/or seizures. Associations found included a higher phenotypical score in patients with sequence variants compared with CNVs and a higher frequency of triangular face (71.1% vs 42.5% in CNVs). Short stature was more frequent in patients with exon 9 variants (62.5% inside vs 27.8% outside exon 9), and the prevalence of intellectual disability/attention deficit hyperactivity disorder/autism spectrum disorder was lower in patients with the c.1903_1907del variant (70.4% vs 89.4% other variants). Presence of macrodontia and comorbidities were associated with larger deletion sizes and hand anomalies with smaller deletions. CONCLUSION: We present a detailed phenotypical description of KBG syndrome in the largest series reported to date of 67 patients, provide evidence of a genotype-phenotype correlation between some KBG features and specific ANKRD11 variants in 340 patients, and propose updated clinical diagnostic criteria based on our findings.

First female with Allan-Herndon-Dudley syndrome and partial deletion of X-inactivation center.

Allan-Herndon-Dudley is an X-linked recessive syndrome caused by pathogenic variants in the SLC16A2 gene. Clinical manifestations are a consequence of impaired thyroid metabolism and aberrant transport of thyroid hormones to the brain. Carrier females are generally asymptomatic and may show subtle symptoms of the disease. We describe a female with a complete Allan-Herndon-Dudley phenotype, carrying a de novo 543-kb deletion of the X chromosome. The deletion encompasses exon 1 of the SLC16A2 gene and JPX and FTX genes; it is known that the latter two genes participate in the X-inactivation process upregulating XIST gene expression. Subsequent studies in the patient demonstrated the preferential expression of the X chromosome with the JPX and FTX deletion.

Coexistence of dyschondrosteosis associated to SHOX deficiency, pseudohypoparathyroidism 1B, and chronic autoimmune thyroiditis: a case report.

We present an unusual case of SHOX deficiency associated with Léri-Weill dyschondrosteosis (LWD), Hashimoto's thyroiditis and pseudohypoparathyroidism 1B in a young woman. To our knowledge, this is the first ever report of these disorders coexisting. At the age of nine years, the proband was diagnosed of hypothyroidism due to Hashimoto's thyroiditis, and developed biochemical abnormalities consistent with hyperphosphatemia, mild hypocalcemia and elevated parathyroid hormone without any clinical symptoms except short stature. Replacement therapy with levothyroxine, calcium and alphacalcidol was initiated. The diagnosis of pseudohypoparathyroidism 1B was confirmed at the age of 17.5 years with the demonstration of methylation alteration at the GNAS locus. At the age of 16 years, 3.5 years after her menarche, she presented clear features of LWD. A large deletion of the SHOX gene was confirmed. Family genetic tests were not doable since she was adopted. We discuss the diagnostic challenges of these coexisting rare endocrinopathies.

Correction to: Panel Discussion: Some Aspects of the Management of Patients with X-Linked Hypophosphataemic Rickets.

In the original article, there is an error in age related reference.

Early-onset nucleotide excision repair disorders with neurological impairment: Clues for early diagnosis and prognostic counseling.

Nucleotide excision repair associated diseases comprise overlapping phenotypes and a wide range of outcomes. The early stages still remain under-investigated and underdiagnosed, even although an early recognition of the first symptoms is of utmost importance for appropriate care and genetic counseling. We systematically collected clinical and molecular data from the literature and from newly diagnosed NER patients with neurological impairment, presenting clinical symptoms before the age of 12 months, including foetal cases. One hundred and eighty-five patients were included, 13 with specific symptoms during foetal life. Arthrogryposis, microcephaly, cataracts, and skin anomalies are the most frequently reported signs in early subtypes. Non ERCC6/CSB or ERCC8/CSA genes are overrepresented compared to later onset cohorts: 19% patients of this cohort presented variants in ERCC1, ERCC2/XPD, ERCC3/XPB or ERCC5/XPG. ERCC5/XPG is even the most frequently involved gene in foetal cases (10/13 cases, [4/7 families]). In this cohort, the mutated gene, the age of onset, the type of disease, severe global developmental delay, IUGR and skin anomalies were associated with earlier death. This large survey focuses on specific symptoms that should attract the attention of clinicians towards early-onset NER diagnosis in foetal and neonatal period, without waiting for the completeness of classical criteria.

Correction to: Panel Discussion: Some Aspects of the Management of Patients with X-Linked Hypophosphataemic Rickets.

In the original article, third author name has been published incorrectly.

Clinical and Molecular Description of 16 Families With Heterozygous IHH Variants.

CONTEXT: Heterozygous variants in the Indian hedgehog gene (IHH) have been reported to cause brachydactyly type A1 and mild hand and feet skeletal anomalies with short stature. Genetic screening in individuals with short stature and mild skeletal anomalies has been increasing over recent years, allowing us to broaden the clinical spectrum of skeletal dysplasias. OBJECTIVE: The objective of this article is to describe the genotype and phenotype of 16 probands with heterozygous variants in IHH. PATIENTS AND METHODS: Targeted next-generation sequencing or Sanger sequencing was performed in patients with short stature and/or brachydactyly for which the genetic cause was unknown. RESULTS: Fifteen different heterozygous IHH variants were detected, one of which is the first reported complete deletion of IHH. None of the patients showed the classical phenotype of brachydactyly type A1. The most frequently observed clinical characteristics were mild to moderate short stature as well as shortening of the middle phalanx on the fifth finger. The identified IHH variants were demonstrated to cosegregate with the short stature and/or brachydactyly in the 13 probands whose family members were available. However, clinical heterogeneity was observed: Two short-statured probands showed no hand radiological anomalies, whereas another 5 were of normal height but had brachydactyly. CONCLUSIONS: Short stature and/or mild skeletal hand defects can be caused by IHH variants. Defects in this gene should be considered in individuals with these findings, especially when there is an autosomal dominant pattern of inheritance. Although no genotype-phenotype correlation was observed, cosegregation studies should be performed and where possible functional characterization before concluding that a variant is causative.

Panel Discussion: Some Aspects of the Management of Patients with X-Linked Hypophosphataemic Rickets.

X-linked hypophosphataemia (XLH) rickets is a rare disease frequently misdiagnosed and mismanaged. Despite having clinical guidelines that offers some therapeutic recommendations based on the clinical experience of experts, physicians still have questions about some important aspects of the diagnosis and treatment of XLH, such as when the disease should be suspected, who should be in charge of the diagnosis, what should be done once the disease is diagnosed, or what therapeutic options are currently available. The objective of this paper is to answer some of the more frequent questions related to the management of patients with XLH by a group of experts participating in a scientific conference on XLH held in Madrid.

Chromosome 1p31.1p31.3 Deletion in a Patient with Craniosynostosis, Central Nervous System and Renal Malformation: Case Report and Review of the Literature.

Interstitial deletions in the short arm of chromosome 1 are infrequent. We report a female with a 1p31.1p31.3 deletion and cloverleaf skull, who presented with renal and central nervous system malformations, cleft palate, severe ocular anomalies, and cutis laxa, in addition to the previously described clinical data present in other cases with deletions encompassing this region, such as developmental delay, seizures, round face with a prominent nose, micro/retrognathia, half-opened mouth, short neck, hand/foot malformations, hernia, congenital heart malformations, and abnormal external genitalia. The deletion spanned ∼18.6 Mb and included a total of 68 OMIM protein coding genes. We have reviewed 17 cases previously described in the literature and in DECIPHER involving the chromosomal region 1p31.1p31.3. Only 3 of these affect the whole region, 9 are partial deletions of this region, and 5 are much smaller deletions. Taking into account the MORBID ID and the haploinsufficiency score of the genes, we go on to propose which genes may explain particular clinical features observed in the patient. IL23R may be responsible for the craniosynostosis, FOXD2 for the renal anomalies, LHX8 for closure defects of the palate, and ST6GALNAC3 for skin anomalies. In summary, we have identified a chromosome 1p31.1p31.3 deletion in a patient with an atypical presentation of craniosynostosis amongst other more typical features observed in individuals with similar deletions.

[Phenotypic variability of the 1q21.1 microdeletion syndrome in members of the same family: relevance of detection of neuropsychiatric disorders for diagnosis of genetic syndromes]. / Variabilidad del fenotipo del sindrome de microdelecion 1q21.1 dentro de una misma familia: importancia de la deteccion de trastornos neuropsiquiatricos para el diagnostico de sindromes geneticos.

INTRODUCTION: 1q21.1 microdeletion syndrome is a caused by a recurrent deletion of the 1q21.1 copy-number variant, which spans 800 kb and includes at least seven genes. It is associated with a variable phenotype. Neuropsychiatric abnormalities have been previously described in many of the previously reported cases, but its true prevalence is unknown. AIM: To illustrate the phenotypic variability in 1q21.1 microdeletion syndrome. CASE REPORTS: Four individuals of the same kindred harboring a 1.74-Mb deletion within 1q21.1 are included. In our patients a heterogeneous phenotype is recognized. Neuropsychiatric disorders or more specifically impulse control disorders were common to all the four cases that we present. CONCLUSIONS: 1q21.1 microdeletion syndrome is phenotypically heterogeneous even among members of the same family. Behavioral or neuropsychiatric abnormalities are frequent. Paucisymptomatic forms with individuals presenting exclusively psychiatric disorders have been identified.

TITLE: Variabilidad del fenotipo del sindrome de microdelecion 1q21.1 dentro de una misma familia: importancia de la deteccion de trastornos neuropsiquiatricos para el diagnostico de sindromes geneticos.Introduccion. El sindrome de microdelecion 1q21.1 esta causado por una delecion recurrente de aproximadamente 800 kb que incluye al menos siete genes y se asocia a un fenotipo variable. Esta variacion en el numero de copias patogenica puede aparecer de novo o ser heredada de uno de los progenitores. La presencia de trastornos psiquiatricos se ha descrito en muchos de los casos publicados, pero se desconoce su prevalencia exacta. Objetivo. Exponer la variabilidad fenotipica de los individuos que presentan una microdelecion 1q21.1. Casos clinicos. Se incluyen cuatro individuos portadores de una delecion de 1,74 Mb en 1q21.1, todos miembros de la misma familia. El estudio genetico del caso indice se llevo a cabo mediante array de hibridacion genomica comparada, y el del resto de familiares mediante hibridacion in situ fluorescente, con una sonda especifica para la region delecionada. Los individuos presentan un fenotipo heterogeneo, y es comun a todos ellos la presencia de alteraciones psiquiatricas o del comportamiento, con un claro predominio de la presencia de trastornos relacionados con las dificultades para el control de impulsos en sus diferentes subtipos. Conclusiones. El sindrome de microdelecion 1q21.1 es fenotipicamente heterogeneo, incluso entre los miembros de una misma familia. Destaca la presencia de alteraciones psiquiatricas o del comportamiento como rasgo comun en todos los pacientes que presentamos. Existen formas paucisintomaticas en las que el individuo portador de la delecion presenta exclusivamente alteraciones psiquiatricas.

Tumor-induced rickets in a child with a central giant cell granuloma: a case report.

Tumor-induced osteomalacia/rickets is a rare paraneoplastic disorder associated with a tumor-producing fibroblast growth factor 23 (FGF23). We present a child with symptoms of rickets as the first clinical sign of a central giant cell granuloma (CGCG) with high serum levels of FGF23, a hormone associated with decreased phosphate resorption. A 3-year-old boy presented with a limp and 6 months later with painless growth of the jaw. On examination gingival hypertrophy and genu varum were observed. Investigations revealed hypophosphatemia, normal 1,25 and 25 (OH) vitamin D, and high alkaline phosphatase. An MRI showed an osteolytic lesion of the maxilla. Radiographs revealed typical rachitic findings. Incisional biopsy of the tumor revealed a CGCG with mesenchymal matrix. The CGCG was initially treated with calcitonin, but the lesions continued to grow, making it necessary to perform tracheostomy and gastrostomy. One year after onset the hyperphosphaturia worsened, necessitating increasing oral phosphate supplements up to 100 mg/kg per day of elemental phosphorus. FGF23 levels were extremely high. Total removal of the tumor was impossible, and partial reduction was achieved after percutaneous computed tomography-guided radiofrequency, local instillation of triamcinolone, and oral propranolol. Compassionate use of cinacalcet was unsuccessful in preventing phosphaturia. The tumor slowly regressed after the third year of disease; phosphaturia improved, allowing the tapering of phosphate supplements, and FGF23 levels normalized. Tumor-induced osteomalacia/rickets is uncommon in children and is challenging for physicians to diagnose. It should be suspected in patients with intractable osteomalacia or rickets. A tumor should be ruled out if FGF23 levels are high.

Novel mutations associated with nephrogenic diabetes insipidus. A clinical-genetic study.

UNLABELLED: Molecular diagnosis is a useful diagnostic tool in primary nephrogenic diabetes insipidus (NDI), an inherited disease characterized by renal inability to concentrate urine. The AVPR2 and AQP2 genes were screened for mutations in a cohort of 25 patients with clinical diagnosis of NDI. Patients presented with dehydration, polyuria-polydipsia, failure to thrive (mean ± SD; Z-height -1.9 ± 2.1 and Z-weight -2.4 ± 1.7), severe hypernatremia (mean ± SD; Na 150 ± 10 mEq/L), increased plasma osmolality (mean ± SD; 311 ± 18 mOsm/Kg), but normal glomerular filtration rate. Genetic diagnosis revealed that 24 male patients were hemizygous for 17 different putative disease-causing mutations in the AVPR2 gene (each one in a different family). Of those, nine had not been previously reported, and eight were recurrent. Moreover, we found those same AVPR2 changes in 12 relatives who were heterozygous carriers. Further, in one female patient, AVPR2 gene study turned out to be negative and she was found to be homozygous for the novel AQP2 p.Ala86Val alteration. CONCLUSION: Genetic analysis presumably confirmed the diagnosis of nephrogenic diabetes insipidus in every patient of the studied cohort. We emphasize that we detected a high presence (50 %) of heterozygous females with clinical NDI symptoms. WHAT IS KNOWN: • In most cases (90 %), inherited nephrogenic diabetes insipidus (NDI) is an X-linked disease, caused by mutations in the AVPR2 gene. • In rare occasions (10 %), it is caused by mutations in the AQP2 gene. What is new: • In this study, we report 10 novel mutations associated with NDI. • We have detected a high presence (50 %) of heterozygous carriers with clinical NDI symptoms.

Expanding the mutation spectrum in 182 Spanish probands with craniosynostosis: identification and characterization of novel TCF12 variants.

Craniosynostosis, caused by the premature fusion of one or more of the cranial sutures, can be classified into non-syndromic or syndromic and by which sutures are affected. Clinical assignment is a difficult challenge due to the high phenotypic variability observed between syndromes. During routine diagnostics, we screened 182 Spanish craniosynostosis probands, implementing a four-tiered cascade screening of FGFR2, FGFR3, FGFR1, TWIST1 and EFNB1. A total of 43 variants, eight novel, were identified in 113 (62%) patients: 104 (92%) detected in level 1; eight (7%) in level 2 and one (1%) in level 3. We subsequently screened additional genes in the probands with no detected mutation: one duplication of the IHH regulatory region was identified in a patient with craniosynostosis Philadelphia type and five variants, four novel, were identified in the recently described TCF12, in probands with coronal or multisuture affectation. In the 19 Saethre-Chotzen syndrome (SCS) individuals in whom a variant was detected, 15 (79%) carried a TWIST1 variant, whereas four (21%) had a TCF12 variant. Thus, we propose that TCF12 screening should be included for TWIST1 negative SCS patients and in patients where the coronal suture is affected. In summary, a molecular diagnosis was obtained in a total of 119/182 patients (65%), allowing the correct craniosynostosis syndrome classification, aiding genetic counselling and in some cases provided a better planning on how and when surgical intervention should take place and, subsequently the appropriate clinical follow up.

In-frame mutations in exon 1 of SKI cause dominant Shprintzen-Goldberg syndrome.

Shprintzen-Goldberg syndrome (SGS) is characterized by severe marfanoid habitus, intellectual disability, camptodactyly, typical facial dysmorphism, and craniosynostosis. Using family-based exome sequencing, we identified a dominantly inherited heterozygous in-frame deletion in exon 1 of SKI. Direct sequencing of SKI further identified one overlapping heterozygous in-frame deletion and ten heterozygous missense mutations affecting recurrent residues in 18 of the 19 individuals screened for SGS; these individuals included one family affected by somatic mosaicism. All mutations were located in a restricted area of exon 1, within the R-SMAD binding domain of SKI. No mutation was found in a cohort of 11 individuals with other marfanoid-craniosynostosis phenotypes. The interaction between SKI and Smad2/3 and Smad 4 regulates TGF-ß signaling, and the pattern of anomalies in Ski-deficient mice corresponds to the clinical manifestations of SGS. These findings define SGS as a member of the family of diseases associated with the TGF-ß-signaling pathway.

Individualised vs fixed dose of oral 17ß-oestradiol for induction of puberty in girls with Turner syndrome: an open-randomised parallel trial.

CONTEXT: Oestrogen induction of pubertal changes in Turner girls may reinforce their psychological well-being and may also optimise final height; however, oestrogen type, dose, and route are not well established. OBJECTIVE: To induce normal pubertal development in Turner girls and ovarian insufficiency with oral 17ß-oestradiol (E(2)), either as individualised dose (ID) or as fixed dose (FD), and to determine whether growth is affected. DESIGN: Open-label randomised, parallel groups, multicentre clinical trial in 48 GH-treated Turner girls. Oral E(2) was given in tablets, either as an ID of 5-15 µg/kg per day during 2 years or as a FD of 0.2 mg daily during the first year followed by 0.5 mg daily during the second year. Main outcome measures were the event of attaining a Tanner breast staging ≥4 (primary), FSH, and auxological variables (secondary). RESULTS: Shorter median time to Tanner staging ≥ B4 in the FD group (733 days) compared with the ID group (818 days) (P=0.046). Higher proportion of girls with Tanner staging ≥ B4 (65%) in the FD group compared with the ID group (42%) (P=0.068). Bone age did not show inadequate acceleration and adult height prediction was maintained in both groups. No oestrogen-related adverse events were reported. CONCLUSIONS: Two-year treatment with oral E(2) can progressively induce normal pubertal development in Turner syndrome. Low-dose oral E(2) given as a FD produces a satisfactory pubertal development not inferior to ID. Treatment was well tolerated and did not interfere with the growth-promoting effect of GH.

Alterations in RAS-MAPK genes in 200 Spanish patients with Noonan and other neuro-cardio-facio-cutaneous syndromes. Genotype and cardiopathy.

INTRODUCTION AND OBJECTIVES: Molecular characterization of congenital heart diseases now includes the not infrequent dysmorphic Noonan syndrome. A study of 6 genes of the RAS-MAPK pathway in Spanish patients is presented: the impact of heart disease, clinical expressivity, and diagnostic yield are investigated. METHODS: The study included 643 patients (and 182 family members) diagnosed by dysmorphologists, cardiologists, and pediatric endocrinologists from 74 tertiary hospitals. Bidirectional sequencing analysis of PTPN11, SOS1, RAF1, BRAF, KRAS and HRAS focused on exons carrying recurrent mutations accounting for 80% to 95% of previously described mutations. RESULTS: Mutations were detected in 230 patients (91 women and 139 men) in 200 (31%) families (172 PTPN11+, 14 SOS1+, 9 RAF1+, 5 BRAF+). There was specific reference to the heart defect suffered in 156 index cases: 103 patients had shown pulmonary stenosis, 12 pulmonary stenosis with hyperthrophic cardiomyopathy, 18 hypertrophic cardiomiopathy, and 14 other cardiopathies; heart disease was absent in 9 index cases. Heart disease had not been documented in 23 of 30 family members with positive genotype and compatible clinical signs. Diagnostic yield was higher (P=.016) for samples from some centers (53%; 14/32) and even from certain professionals (64%; 9/14; P=.019). Characterization rate was 18% in patients for whom clinical data were not available. Genotyping led to a more precise diagnosis in 26 patients. CONCLUSIONS: Most patients (94%) with a positive genotype had known congenital heart disease, 79% pulmonary stenosis and 12% hyperthrophic cardiomyopathy. Cardiopathy had not been documented in 76% of family members carrying the mutation. Molecular study is a useful tool in these syndromes but a more rigorous clinical diagnosis should be intended as well.