Unexpected findings in cervical spine in spondylometaphyseal dysplasia Sutcliff type FN1-related.

The autosomal dominant spondylometaphyseal dysplasia Sutcliff type or corner fracture type FN1-related is characterized by a combination of metaphyseal irregularities simulating fractures ("corner fractures"), developmental coxa vara, and vertebral changes. It is linked to heterozygous mutations in FN1 and COL2A1. Vertebral changes as delayed vertebral ossification, ovoid vertebral bodies, anterior vertebral wedging, and platyspondyly have been observed in this condition, while odontoid abnormalities have not been reported. We report an odontoid anomaly in a girl with SMD-CF FN1-related showing the heterozygous variant c.505T>A; p.(Cys169Ser), presenting at 11.9 years of age with acute quadriparesis. Images showed spinal cord compression and injury associated with os odontoideum and C1-C2 instability. She required decompression and instrumented occipitocervical stabilization, suffering from residual paraparesis. This paper describes the first case of SMD-CF FN1-related accompanied by odontoid anomalies.

Challenges in genetic diagnosis, co-occurrence of 22q11.2 deletion syndrome and Noonan syndrome.

Noonan syndrome (NS) is caused by pathogenic variants in genes involved in the RAS/MAPK pathway. On the other hand, 22q11.2 Deletion Syndrome (22q11.2DS) is caused by heterozygous microdeletion on chromosome 22q11.2. The clinical characteristics of both syndromes are expected to be relatively distinct, and, in fact, there is only one report of these syndromes occurring together, but on daily clinical practice and especially in early childhood phenotypes may overlap. In this study, we describe a patient with NS and 22q11.2DS features harboring a heterozygous 2.54 Mb deletion of chromosome 22q11.2 and a variant in LZTR1, c.1531G > A p.(Val511Met). In 1993, Wilson et al reported a patient with both 22q11.2DS and NS, proposing that probably more than one gene is deleted in the proband and that one of the deleted genes is responsible for Noonan's phenotype. In our patient, one of the deleted genes within the 22q11.2 region was the LZTR1 gene which was associated with NS in 2015. This case also highlights the importance of the long-term patients' follow-up to detect evolutionary changes that may appear in the phenotype and alerts clinicians of the co-occurrence of two syndromes that may manifest over time.

Noonan syndrome with loose anagen hair with variants in the PPP1CB gene: First familial case reported.

Rasopathies are a group of phenotypically overlapping conditions that include Noonan, Noonan with multiple lentigines, Noonan with loose anagen hair, Costello, Cardio-facio-cutaneous, and Neurofibromatosis-Noonan syndromes. Noonan syndrome with loose anagen hair (NS-LAH) is clinically characterized by prominent forehead, macrocephaly, growth hormone deficiency, sparse, loose and slow-growing anagen hair, hyperpigmented skin with eczema or ichthyosis, mild psychomotor delays, hypernasal voices, and attention deficit hyperactivity disorder. Variants in SHOC2 are responsible for the majority of the cases. Gripp et al. identified four unrelated individuals with similar phenotype to NS-LAH with pathogenic variants in PPP1CB. In this study, we present one family and one patient with NS-LAH and variants in PPP1CB. The first patient belongs to a family with a likely pathogenic variant, c.545T>A (p.Met182Lys), the first family published so far with a variant in this gene. The second patient harbors a de novo pathogenic variant, c.146C>G (p.Pro49Arg). This study presents two additional patients with this rare syndrome in order to increase the clinical characterization of the syndrome and provide more evidence of the pathogenicity of the c.545T>A (p.Met182Lys) variant in PPP1CB, a gene recently associated with NS-LAH.

Providing more evidence on LZTR1 variants in Noonan syndrome patients.

Noonan syndrome (NS, OMIM 163950) is a common autosomal dominant RASopathy caused mainly by gain-of-function germline pathogenic variants in genes involved in the RAS/MAPK signaling pathway. LZTR1 gene has been associated with both dominant and recessive NS. Here, we present seven patients with NS and variants in the LZTR1 gene from seven unrelated families, 14 individuals in total. The detection rAte of LZTR1 variants in our NS cohort was 4% similar to RAF1 and KRAS genes, indicating that variants in this gene might be frequent among our population. Three different variants were detected, c.742G>A (p.Gly248Arg), c.360C>A (p.His120Gln), and c.2245T>C (p.Tyr749His). The pathogenic variant c.742G>A (p.Gly248Arg) was found in five/seven patients. In our cohort 50% of patients presented heart defects and neurodevelopment delay or learning disabilities, short stature was present in 21% of them and one patient had acute lymphoblastic leukemia. This study broadens the spectrum of variants in the LZTR1 gene and provides increased knowledge of the clinical phenotypes observed in Argentinean NS patients.

Variable pulmonary manifestations in Chitayat syndrome: Six additional affected individuals.

Hand hyperphalangism leading to shortened index fingers with ulnar deviation, hallux valgus, mild facial dysmorphism and respiratory compromise requiring assisted ventilation are the key features of Chitayat syndrome. This condition results from the recurrent heterozygous missense variant NM_006494.2:c.266A>G; p.(Tyr89Cys) in ERF on chromosome 19q13.2, encoding the ETS2 repressor factor (ERF) protein. The pathomechanism of Chitayat syndrome is unknown. To date, seven individuals with Chitayat syndrome and the recurrent pathogenic ERF variant have been reported in the literature. Here, we describe six additional individuals, among them only one presenting with a history of assisted ventilation, and the remaining presenting with variable pulmonary phenotypes, including one individual without any obvious pulmonary manifestations. Our findings widen the phenotype spectrum caused by the recurrent pathogenic variant in ERF, underline Chitayat syndrome as a cause of isolated skeletal malformations and therefore contribute to the improvement of diagnostic strategies in individuals with hand hyperphalangism.

Rubinstein-Taybi syndrome in diverse populations.

Rubinstein-Taybi syndrome (RSTS) is an autosomal dominant disorder, caused by loss-of-function variants in CREBBP or EP300. Affected individuals present with distinctive craniofacial features, broad thumbs and/or halluces, and intellectual disability. RSTS phenotype has been well characterized in individuals of European descent but not in other populations. In this study, individuals from diverse populations with RSTS were assessed by clinical examination and facial analysis technology. Clinical data of 38 individuals from 14 different countries were analyzed. The median age was 7 years (age range: 7 months to 47 years), and 63% were females. The most common phenotypic features in all population groups included broad thumbs and/or halluces in 97%, convex nasal ridge in 94%, and arched eyebrows in 92%. Face images of 87 individuals with RSTS (age range: 2 months to 47 years) were collected for evaluation using facial analysis technology. We compared images from 82 individuals with RSTS against 82 age- and sex-matched controls and obtained an area under the receiver operating characteristic curve (AUC) of 0.99 (p < .001), demonstrating excellent discrimination efficacy. The discrimination was, however, poor in the African group (AUC: 0.79; p = .145). Individuals with EP300 variants were more effectively discriminated (AUC: 0.95) compared with those with CREBBP variants (AUC: 0.93). This study shows that clinical examination combined with facial analysis technology may enable earlier and improved diagnosis of RSTS in diverse populations.

Turner syndrome in diverse populations.

Turner syndrome (TS) is a common multiple congenital anomaly syndrome resulting from complete or partial absence of the second X chromosome. In this study, we explore the phenotype of TS in diverse populations using clinical examination and facial analysis technology. Clinical data from 78 individuals and images from 108 individuals with TS from 19 different countries were analyzed. Individuals were grouped into categories of African descent (African), Asian, Latin American, Caucasian (European descent), and Middle Eastern. The most common phenotype features across all population groups were short stature (86%), cubitus valgus (76%), and low posterior hairline 70%. Two facial analysis technology experiments were conducted: TS versus general population and TS versus Noonan syndrome. Across all ethnicities, facial analysis was accurate in diagnosing TS from frontal facial images as measured by the area under the curve (AUC). An AUC of 0.903 (p < .001) was found for TS versus general population controls and 0.925 (p < .001) for TS versus individuals with Noonan syndrome. In summary, we present consistent clinical findings from global populations with TS and additionally demonstrate that facial analysis technology can accurately distinguish TS from the general population and Noonan syndrome.

Williams-Beuren syndrome in diverse populations.

Williams-Beuren syndrome (WBS) is a common microdeletion syndrome characterized by a 1.5Mb deletion in 7q11.23. The phenotype of WBS has been well described in populations of European descent with not as much attention given to other ethnicities. In this study, individuals with WBS from diverse populations were assessed clinically and by facial analysis technology. Clinical data and images from 137 individuals with WBS were found in 19 countries with an average age of 11 years and female gender of 45%. The most common clinical phenotype elements were periorbital fullness and intellectual disability which were present in greater than 90% of our cohort. Additionally, 75% or greater of all individuals with WBS had malar flattening, long philtrum, wide mouth, and small jaw. Using facial analysis technology, we compared 286 Asian, African, Caucasian, and Latin American individuals with WBS with 286 gender and age matched controls and found that the accuracy to discriminate between WBS and controls was 0.90 when the entire cohort was evaluated concurrently. The test accuracy of the facial recognition technology increased significantly when the cohort was analyzed by specific ethnic population (P-value < 0.001 for all comparisons), with accuracies for Caucasian, African, Asian, and Latin American groups of 0.92, 0.96, 0.92, and 0.93, respectively. In summary, we present consistent clinical findings from global populations with WBS and demonstrate how facial analysis technology can support clinicians in making accurate WBS diagnoses.

Contribution of Mitochondrial DNA Heteroplasmy to the Congenital Cardiac and Palatal Phenotypic Variability in Maternally Transmitted 22q11.2 Deletion Syndrome.

Congenital heart disease (CHD) and palatal anomalies (PA), are among the most common characteristics of 22q11.2 deletion syndrome (22q11.2DS), but they show incomplete penetrance, suggesting the presence of additional factors. The 22q11.2 deleted region contains nuclear encoded mitochondrial genes, and since mitochondrial function is critical during development, we hypothesized that changes in the mitochondrial DNA (mtDNA) could be involved in the intrafamilial variability of CHD and PA in cases of maternally inherited 22q11.2DS. To investigate this, we studied the transmission of heteroplasmic mtDNA alleles in seventeen phenotypically concordant and discordant mother-offspring 22q11.2DS pairs. We sequenced their mtDNA and identified 26 heteroplasmic variants at >1% frequency, representing 18 transmissions. The median allele frequency change between a mother and her child was twice as much, with a wider distribution range, in PA discordant pairs, p-value = 0.039 (permutation test, 11 concordant vs. 7 discordant variants), but not in CHD discordant pairs, p-value = 0.441 (9 vs. 9). Only the variant m.9507T>C was considered to be pathogenic, but it was unrelated to the structural phenotypes. Our study is novel, yet our results are not consistent with mtDNA variation contributing to PA or CHD in 22q11.2DS. Larger cohorts and additional factors should be considered moving forward.

Clinical and molecular characterization of children with Noonan syndrome and other RASopathies in Argentina. / Caracterización clínica y molecular de niños con síndrome de Noonan y otras RASopatías en Argentina.

INTRODUCTION: RASopathies are a set of syndromes with phenotypic overlapping features caused by gene mutations involved in the RAS/MAPK pathway. They are autosomal dominantly inherited and share common clinical characteristics, including short stature, craniofacial dysmorphisms, congenital heart disease, ectodermal manifestations, and a higher risk for cancer. A molecular diagnosis is a key factor. OBJECTIVE: To identify PTPN11, SOS1, RAF1, BRAF, and HRAS mutations and compare the main clinical characteristics of patients with molecular confirmation. Population and methods. Children with a clinical diagnosis of RASopathy assessed between August 2013 and February 2017. RESULTS: Mutations were identified in 71 % (87/122) of patients. The molecular test confirmed diagnosis in 73 % of patients with Noonan syndrome. The most prevalent mutation was c.922A>G (p.Asn308Asp) in the PTPN11 gene. A previously undescribed variant in RAF1 was detected: c.1467G>>C (p.Leu489Phe). Cardiofaciocutaneous syndrome was confirmed in 67 % of cases with BRAF mutations. Costello syndrome and Noonan syndrome with multiple lentigines were confirmed in all cases. CONCLUSION: The confirmation of clinical diagnosis allowed for a more accurate differential diagnosis. The prevalence of PTPN11 (58 %), SOS1 (10 %), and RAF1 mutations (5 %) in children with Noonan syndrome, of PTPN11 mutations (100 %) in those with Noonan syndrome with multiple lentigines, of BRAF mutations (67 %) in those with cardiofaciocutaneous syndrome, and of HRAS mutations (100 %) in those with Costello syndrome was determined.

Introducción. Las RASopatías son un conjunto de síndromes fenotípicamente superpuestos causados por mutaciones en genes implicados en la vía RAS/MAPK. La herencia es autosómica dominante, presentan características clínicas comunes, como baja talla, dismorfias craneofaciales, cardiopatía congénita, manifestaciones ectodérmicas y mayor riesgo de cáncer. El diagnóstico molecular es clave. Objetivo. Identificar mutaciones en los genes PTPN11, SOS1, RAF1, BRAF y HRAS, y comparar las principales características clínicas en pacientes con confirmación molecular. Población y métodos. Se estudiaron niños con diagnóstico clínico de RASopatía evaluados entre agosto de 2013 y febrero de 2017. Resultados. Se identificaron mutaciones en el 71 % (87/122) de los pacientes. El estudio molecular confirmó el diagnóstico en el 73 % de los pacientes con síndrome de Noonan. La mutación más prevalente fue c.922A>G (p.Asn308Asp) en el gen PTPN11. Se detectó una variante no descrita en RAF1, c.1467G>C (p.Leu489Phe). Se confirmó el síndrome cardiofaciocutáneo en el 67 % de los casos con mutaciones en el gen BRAF. El síndrome de Costello y el síndrome de Noonan con múltiples lentigos se confirmaron en todos los casos. Conclusión. La confirmación del diagnóstico clínico permitió un diagnóstico diferencial más preciso. Se determinó la prevalencia de las mutaciones en PTPN11 (el 58 %), SOS1 (el 10 %) y RAF1 (el 5 %) en niños con síndrome de Noonan, en PTPN11 (el 100 %) en el síndrome de Noonan con múltiples lentigos, en BRAF (el 67 %) en el síndrome cardiofaciocutáneo y en HRAS (el 100 %) en el síndrome de Costello.

[Pai syndrome: Two new cases with unusual manifestations]. / Síndrome de Pai: dos nuevos casos con manifestaciones inusuales.

Pai syndrome is a very rare congenital disorder characterized by medial cleft lip, nasal and facial cutaneous polyps, and pericallosal lipoma. Broad phenotypic variability exists in this condition. Neurodevelopment is usually normal. Up to date 42 cases have been reported in the literature. Different types of inheritance have been proposed, but most cases are sporadic. No gene has been identified. We report two cases with Pai syndrome, one of them with novel clinical findings as vertebral segmentation defects and choroidal osteoma.

El síndrome de Pai se describe como la presencia de 3 anomalías congénitas: fisura de labio medial, pólipos cutáneos nasales y faciales, y lipoma pericallosal. La expresión clínica es variable. El desarrollo neuromadurativo suele ser normal. Existen 42 casos descritos en la literatura. Se proponen distintos tipos de herencia, pero, hasta la actualidad, no existe un gen asignado para esta patología. Se presentan dos pacientes con síndrome de Pai, uno de ellos con hallazgos clínicos aún no descritos (defectos de segmentación vertebral y osteoma coroideo).

Caracterización clínica y molecular de niños con síndrome de Noonan y otras RASopatías en Argentina / Clinical and molecular characterization of children with Noonan syndrome and other RASopathies in Argentina

Introducción. Las RASopatías son un conjunto de síndromes fenotípicamente superpuestos causados por mutaciones en genes implicados en la vía RAS/MAPK. La herencia es autosómica dominante, presentan características clínicas comunes, como baja talla, dismorfias craneofaciales, cardiopatia congénita, manifestaciones ectodérmicas y mayor riesgo de cáncer. El diagnóstico molecular es clave. Objetivo. Identificar mutaciones en los genes PTPN11, SOS1,RAF1, BRAFy HRAS,y comparar las principales características clínicas en pacientes con confirmación molecular. Población y métodos. Se estudiaron niños con diagnóstico clínico de RASopatía evaluados entre agosto de 2013 y febrero de 2017. Resultados. Se identificaron mutaciones en el 71 % (87/122) de los pacientes. El estudio molecular confirmó el diagnóstico en el 73 % de los pacientes con síndrome de Noonan. La mutación más prevalente fue c.922A>G (p.Asn308Asp) en el gen PTPN11. Se detectó una variante no descrita en RAF1, c.1467G>C (p.Leu489Phe). Se confirmó el sindrome cardiofaciocutáneo en el 67 % de los casos con mutaciones en el gen BRAF. El síndrome de Costello y el síndrome de Noonan con múltiples lentigos se confirmaron en todos los casos. Conclusión. La confirmación del diagnóstico clínico permitió un diagnóstico diferencial más preciso. Se determinó la prevalencia de las mutaciones en PTPN11 (el 58 %), SOS1 (el 10 %) y RAF1 (el 5 %) en niños con síndrome de Noonan, en PTPN11 (el 100 %) en el sindrome de Noonan con múltiples lentigos, en BRAF (el 67 %) en el síndrome cardiofaciocutáneo y en HRAS (el 100 %) en el sindrome de Costello.

Introduction. RASopathies are a set of syndromes with phenotypic overlapping features caused by gene mutations involved in the RAS/MAPK pathway. They are autosomal dominantly inherited and share common clinical characteristics, including short stature, craniofacial dysmorphisms, congenital heart disease, ectodermal manifestations, and a higher risk for cancer. A molecular diagnosis is a key factor. Objective. To identify PTPN11, SOS1, RAF1, BRAF, and HRAS mutations and compare the main clinical characteristics of patients with molecular confirmation. Population and methods. Children with a clinical diagnosis of RASopathy assessed between August 2013 and February 2017. Results. Mutations were identified in 71 % (87/122) of patients. The molecular test confirmed diagnosis in 73 % of patients with Noonan syndrome. The most prevalent mutation was c.922A>G (p.Asn308Asp) in the PTPN11 gene. A previously undescribed variant in RAF1 was detected: c.1467G>C (p.Leu489Phe). Cardiofaciocutaneous syndrome was confirmed in 67 % of cases with BRAF mutations. Costello syndrome and Noonan syndrome with multiple lentigines were confirmed in all cases. Conclusion. The confirmation of clinical diagnosis allowed for a more accurate differential diagnosis. The prevalence of PTPN11 (58 %), SOS1 (10 % ), and RAF1 mutations (5 %) in children with Noonan syndrome, of PTPN11 mutations (100 %) in those with Noonan syndrome with multiple lentigines, of BRAF mutations (67 %) in those with cardiofaciocutaneous syndrome, and of HRAS mutations (100 %) in those with Costello syndrome was determined.

Síndrome de Pai: dos nuevos casos con manifestaciones inusuales / Pai syndrome: Two new cases with unusual manifestations

El síndrome de Pai se describe como la presencia de 3 anomalías congénitas: fisura de labio medial, pólipos cutáneos nasales y faciales, y lipoma pericallosal. La expresión clínica es variable. El desarrollo neuromadurativo suele ser normal. Existen 42 casos descritos en la literatura. Se proponen distintos tipos de herencia, pero, hasta la actualidad, no existe un gen asignado para esta patología. Se presentan dos pacientes con síndrome de Pai, uno de ellos con hallazgos clínicos aún no descritos (defectos de segmentación vertebral y osteoma coroideo).

Pai syndrome is a very rare congenital disorder characterized by medial cleft lip, nasal and facial cutaneous polyps, and pericallosal lipoma. Broad phenotypic variability exists in this condition. Neurodevelopment is usually normal. Up to date 42 cases have been reported in the literature. Different types of inheritance have been proposed, but most cases are sporadic. No gene has been identified. We report two cases with Pai syndrome, one of them with novel clinical findings as vertebral segmentation defects and choroidal osteoma.