Fluorescence in situ hybridization (FISH) as an irreplaceable diagnostic tool for Williams-Beuren syndrome in developing countries: a literature review.

OBJECTIVE: The aim of this study was to sum up and characterize all Williams-Beuren syndrome cases diagnosed by fluorescence in situ hybridization (FISH) since its implementation, as well as to discuss FISH as a cost-effective methodology in developing countries. DATA SOURCE: From January 1986 to January 2022, articles were selected using the databases in PubMed (Medline) and SciELO. The following terms were used: Williams syndrome and In Situ Hybridization, Fluorescence. Inclusion criteria included Williams-Beuren syndrome cases diagnosed by FISH with a stratified phenotype of each patient. Only studies written in English, Spanish, and Portuguese were included. Studies with overlapping syndromes or genetic conditions were excluded. DATA SYNTHESIS: After screening, 64 articles were included. A total of 205 individuals with Williams-Beuren syndrome diagnosed by FISH were included and further analyzed. Cardiovascular malformations were the most frequent finding (85.4%). Supravalvular aortic stenosis (62.4%) and pulmonary stenosis (30.7%) were the main cardiac alterations described. CONCLUSIONS: Our literature review reinforces that cardiac features may be the key to early diagnosis in Williams-Beuren syndrome patients. In addition, FISH may be the best diagnostic tool for developing nations that have limited access to new technologic resources.

Congenital Heart Defects and 22q11.2 Deletion Syndrome: A 20-Year Update and New Insights to Aid Clinical Diagnosis.

Congenital heart defects (CHDs) are one of the most prevalent clinical features described in individuals diagnosed with 22q11.2 deletion syndrome (22q11.2DS). Therefore, cardiac malformations may be the main finding to refer for syndrome investigation, especially in individuals with a mild phenotype. Nowadays, different cytogenetic methodologies have emerged and are used routinely in research laboratories. Hence, choosing an efficient technology and providing an accurate interpretation of clinical findings is crucial for 22q11.2DS patient's diagnosis. This systematic review provides an update of the last 20 years of research on 22q11.2DS patients with CHD and the investigation process behind each diagnosis. A search was performed in PubMed, Embase, and LILACS using all entry terms to DiGeorge syndrome, CHDs, and cytogenetic analysis. After screening, 60 papers were eligible for review. We present a new insight of ventricular septal defect as a possible pivotal cardiac finding in individuals with 22q11.2DS. Also, we describe molecular technologies and cardiac evaluation as valuable tools in order to guide researchers in future investigations.

Fluorescence in situ hybridization (FISH) as an irreplaceable diagnostic tool for Williams-Beuren syndrome in developing countries: a literature review / Hibridização in situ fluorescente (FISH) como ferramenta diagnóstica insubstituível para a síndrome de Williams-Beuren em países em desenvolvimento: uma revisão de literatura

ABSTRACT Objective: The aim of this study was to sum up and characterize all Williams-Beuren syndrome cases diagnosed by fluorescence in situ hybridization (FISH) since its implementation, as well as to discuss FISH as a cost-effective methodology in developing countries. Data source: From January 1986 to January 2022, articles were selected using the databases in PubMed (Medline) and SciELO. The following terms were used: Williams syndrome and In Situ Hybridization, Fluorescence. Inclusion criteria included Williams-Beuren syndrome cases diagnosed by FISH with a stratified phenotype of each patient. Only studies written in English, Spanish, and Portuguese were included. Studies with overlapping syndromes or genetic conditions were excluded. Data synthesis After screening, 64 articles were included. A total of 205 individuals with Williams-Beuren syndrome diagnosed by FISH were included and further analyzed. Cardiovascular malformations were the most frequent finding (85.4%). Supravalvular aortic stenosis (62.4%) and pulmonary stenosis (30.7%) were the main cardiac alterations described. Conclusions: Our literature review reinforces that cardiac features may be the key to early diagnosis in Williams-Beuren syndrome patients. In addition, FISH may be the best diagnostic tool for developing nations that have limited access to new technologic resources.

RESUMO Objetivo: Caracterizar todos os casos de síndrome de Williams-Beuren (SWB) diagnosticados por hibridização in situ fluorescente (FISH) desde sua implementação, assim como discutir a relação custo-benefício da metodologia de FISH em países em desenvolvimento. Fontes de dados: Entre janeiro de 1986 e janeiro de 2022 foi realizada uma busca nas bases de dados PubMed (Medical Literature Analysis and Retrieval System Online — Medline) e Scientific Electronic Library Online (SciELO) usando os seguintes termos: síndrome de Williams e hibridização in situ fluorescente. O critério de inclusão utilizado foi conter a descrição detalhada de caso(s) de SWB por FISH. Apenas estudos escritos em inglês, espanhol e português foram incluídos. Trabalhos que apresentavam sobreposição de síndromes/condições genéticas foram excluídos. Síntese dos dados: Após os processos de inclusão, 64 artigos e 205 indivíduos com SWB diagnosticados por meio do método de FISH foram incluídos. O achado mais frequente entre os indivíduos foi a presença de algum tipo de malformação cardíaca (85,4%). A estenose aórtica supravalvar (62,4%) e a estenose pulmonar (30,7%) foram as alterações cardíacas mais descritas. A maioria dos estudos era proveniente dos continentes Europa, Ásia e América do Norte. Conclusões: A presente revisão de literatura reitera que as malformações cardíacas podem ser a chave para o diagnóstico precoce em pacientes com SWB. Ainda, a técnica de FISH parece ser a melhor ferramenta de diagnóstico para os países em desenvolvimento, cujo acesso às novas tecnologias ainda é escasso.

A child with cat-eye syndrome and oculo-auriculo-vertebral spectrum phenotype: A discussion around molecular cytogenetic findings.

Cat eye syndrome (CES) is a rare chromosomal disorder that may be evident at birth. A small supernumerary chromosome is present, frequently has 2 centromeres, is bisatellited, and represents an inv dup(22)(q11) in those affected. It's known that the 22q11 region is associated with disorders involving higher and lower gene dosages. Conditions such as CES, 22q11 microduplication syndrome (Dup22q11) and oculoauriculovertebral spectrum phenotype (OAVS) may share genes belonging to this same region, which is known to have a predisposition to chromosomal rearrangements. The conditions, besides being related to chromosome 22, also share similar phenotypes. Here we have added a molecular evaluation update and results found of the first patient described with CES and OAVS phenotype, trying to explain the potential mechanism involved in the occurrence of this association.

Pseudohypoparathyroidism with Ectopic Calcification and 22q11 Deletion Syndrome: A Rare Case.

Ectopic calcification in soft tissue is associated with several disorders including pseudohypoparathyroidism (PHP), which is characterized by resistance or nonresponse to parathyroid hormone (PTH) function. Association between PHP and 22q11DS, also known as DiGeorge syndrome, is rare, especially in children. We describe a newborn girl diagnosed with 22q11DS, presenting ectopic calcifications in soft tissue and suspicion of PHP. PTH function showed values close to the upper limit of the reference value. Radiology showed bone callus in the right wrist. PHP can be a new clinical finding associated with 22q11DS. Parathyroid function investigation in individuals with 22q11DS, presenting bone dysmorphisms and/or calcium metabolism alterations, should be considered.

Candidate genes of oculo-auriculo-vertebral spectrum in 22q region: A systematic review.

Oculo-auriculo-vertebral spectrum (hemifacial microsomia/OAVS, OMIM #164210) is a heterogenous and congenital condition caused by a morphogenesis defect of the first and second pharyngeal arches. Etiology includes unknown genetic, environmental factors and chromosomal alterations, which 22q11.2 region is the most frequently reported. Several candidate genes for OAVS have been proposed; however, none has been confirmed as causative of the phenotype. This review aims to sum up all clinical and molecular findings in 22q region of individuals diagnosed with OAVS and to investigate genes that may be involved in the development of the spectrum. A search was performed in PubMed using all entry terms to OAVS and Chromosome 22q11. After screening, 11 papers were eligible for review. Deletions and duplications in the q11.2 region were the most frequent (18/22) alterations reported and a total of 68 genes were described. Our systematic review reinforces the hypothesis that 22q11 region is a candidate locus for OAVS as well as CLTCL1, GSC2, HIRA, MAPK1, TBX1, and YPEL1 as potential candidates genes for genotype-phenotype correlation. Complementary studies regarding genes interaction involved in the 22q11 region are still necessary in the search for a genotype-phenotype association, since the diagnosis of OAVS is a constant medical challenge.

Congenital Heart Defects and Dysmorphic Facial Features in Patients Suspicious of 22q11.2 Deletion Syndrome in Southern Brazil.

22q11.2 deletion syndrome (22q11.2DS) is considered one of the most frequently observed chromosomal abnormalities in association with congenital heart disease (CHD), which can also include some combination of other features. Thus, the aim of this work was to verify the profile of dysmorphic features and heart defects found in patients referred to a reference center in Southern Brazil with clinical findings suggestive of 22q11.2DS. In the overall sample group, only patients with dysmorphic facial features (skull, eyes, ear, and nose) associated with CHD (obstructive pulmonary valve ring, truncus arteriosus, and bicuspid aortic valve associated with atrial septal defect and/or right aortic arch) had a 22q11.2 deletion. These findings proved to be reliable clinical criteria for referral to perform fluorescent in situ hybridization investigation for 22q11.2 deletion.

Microarray-Based Comparative Genomic Hybridization, Multiplex Ligation-Dependent Probe Amplification, and High-Resolution Karyotype for Differential Diagnosis Oculoauriculovertebral Spectrum: A Systematic Review.

Oculoauriculovertebral spectrum (OAVS) is a rare class of heterogenous congenital craniofacial malformation conditions of unknown etiology. Although classic OAVS has been described as hemifacial microsomia with facial asymmetry and microtia, there is no consensus regarding clinical criteria for diagnosis or genetic cause. This systematic review aims to assess the applicability of high-resolution (HR) karyotype, fluorescence in situ hybridization, multiplex ligation-dependent probe amplification (MLPA), and microarray-based comparative genomic hybridization (array-CGH) for differential diagnosis of OAVS. A search was performed in PubMed and Web of Science using all entry terms to the following descriptors: Goldenhar's syndrome, cytogenetic analysis, hybridization in situ, fluorescent, comparative genomic hybridization, multiplex polymerase chain reaction, whole genome sequencing, and karyotype analysis methods. After screening, 25 articles met eligibility. Of the included studies, 59 individuals had a genetic alteration identified. Array-CGH, MLPA, and HR karyotype appear to be viable approaches for molecular diagnosis in OAVS. Heterogeneity is a hallmark of OAVS. Establishing an enhanced framework for diagnosis would inform clinical decision making, and better resource utilization could improve health care facility efficiency and economy.