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BACKGROUND: Limb-girdle muscular dystrophies constitute a heterogeneous group of neuromuscular diseases, both clinically and genetically. Limb-girdle muscular dystrophy by alpha-sarcoglycan deficiency or LGMD R3 α-sarcoglycan-related is a subtype of the autosomal recessive sarcoglycanopathies caused by variants in the alpha-sarcoglycan gene (SGCA) at 17q21.33. It appears in childhood by progressive weakness of pelvic and/or scapular girdle muscles and calf hypertrophy, with a wide range of clinical inter- and intra-familial clinical variability. AIMS: Our report extends the molecular spectrum of SGCA gene with the identification of variant disease causing and will help for better management of patients and genetic counseling of families. METHODS: In our study, seven unrelated families presented a clinical and paraclinical picture consistent with alpha-sarcoglycanopathy. A molecular study using Next-Generation Sequencing (NGS) was carried out on them. RESULTS: Six different homozygous variants of the SGCA gene were identified in the patients analyzed, including four previously reported variants and two novel variants predicted to be deleterious by the prediction tools. CONCLUSIONS: Our results expand the spectrum of variants in Moroccan patients with sarcoglycanopathy, specifically LGMDR3, most importantly as this form is not common in the Moroccan population.
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Introduction: Currarino syndrome is a rare syndrome with multiple congenital anomalies including sacral agenesis, anorectal malformation, and presence of a presacral mass. Currarino syndrome is considered to be an autosomal dominant inherited disorder, with low penetrance and variable expressivity, but sporadic cases have also been reported. Mutations in MNX1 gene, mapped to 7q36, are the main causes of this syndrome. To the best of our knowledge, less than 400 cases of this syndrome have been mentioned in the literature. Currarino syndrome is often seen in children and considered to be rare in adults; it is mostly found as incidental finding and suspected to be underdiagnosed. Case Presentation: Recognizing the rarity of this syndrome, we present here two siblings with incomplete form of Currarino syndrome combined with microcephaly and intellectual disability. Banding and molecular cytogenetics were used to characterize the origin of this disorder. Banding cytogenetics together with molecular cytogenetics revealed an unbalanced translocation t(7;21)(q36.2;p11.3)mat, leading to a deletion of the 7q36 region in both affected children. Conclusion: This report highlights the importance of cytogenetics in diagnosis of rare genetic syndromes, with impact on genetic counseling of patients and their families. To the best of our knowledge, this is the first Moroccan Currarino syndrome case due to an unbalanced translocation leading to a der(7)t(7;21)(q36.2;p11.3). Also, this is the first Currarino syndrome case associated with a deletion in 7q36 to be reported in Morocco.
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Infertility affects around 20% of couples of reproductive age; however, in some societies, as many as one-third of couples are unable to conceive. Different factors contribute to the decline of male fertility, such us environmental and professional exposure to endocrine disruptors, oxidative stress, and life habits with the risk of de novo epigenetics dysregulation. Since the fantastic development of new "omes and omics" technologies, the contribution of inherited or de novo genomes and epigenome disorders to male infertility have been further elucidated. Many other techniques have become available to andrology laboratories for the investigation of genome and epigenome integrity and the maturation and the competency of spermatozoa. All these new methods of assessment are highlighting the importance of genetics and epigenetics investigation for assisted reproduction pathology and for supporting professionals in counselling patients and proposing different management strategies for male infertility. This aims to improve clinical outcomes while minimizing the risk of genetics or health problems at birth.
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Epigenoma , Infertilidad Masculina , Recién Nacido , Humanos , Masculino , Epigenoma/genética , Retroalimentación , Infertilidad Masculina/genética , Reproducción , EspermatozoidesRESUMEN
Introduction: The majority of small supernumerary marker chromosomes (sSMCs) are derived from one single chromosome. Complex sSMCs, on the other hand, consist of genetic material derived from more than one, normally two chromosomes. Complex sSMCs involving chromosomes 8 and 14 are rarely encountered. Case presentation: We present here a 14-month-old boy born from an unrelated couple. At birth, the baby was hypotonic and had a cleft lip and palate, as well as ocular involvement. Throughout the course of development, the baby experienced feeding difficulties, stunted growth, and delayed psychomotor development. Banding together with molecular cytogenetics revealed a balanced maternal translocation t(8;14)(p22.3;q21)mat, leading due to meiotic 3:1 segregation to a partial trisomy of chromosomes 8 and 14 in the affected boy. Discussion/Conclusion: This report highlights the importance of cytogenetics in diagnosis of rare genetic disorders, with impact on genetic counselling of patients and their families. There are three comparable cases in the literature involving both chromosomes 8 and 14, but with different breakpoints; the complex sSMC derived from chromosomes 8 and 14 in this case, characterized as der(14)t(8;14) (p22.3;q21)mat.
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Noonan syndrome (NS; OMIM 163950) is an autosomal dominant RASopathy with variable clinical expression and genetic heterogeneity. Clinical manifestations include characteristic facial features, short stature, and cardiac anomalies. Variants in protein-tyrosine phosphatase, non-receptor-type 11 (PTPN11), encoding SHP-2, account for about half of NS patients, SOS1 in approximately 13%, RAF1 in 10%, and RIT1 each in 9%. Other genes have been reported to cause NS in less than 5% of cases including SHOC2, RASA2, LZTR1, SPRED2, SOS2, CBL, KRAS, NRAS, MRAS, PRAS, BRAF, PPP1CB, A2ML1, MAP2K1, and CDC42. Several additional genes associated with a Noonan syndrome-like phenotype have been identified. Clinical presentation and variants in patients with Noonan syndrome are this study's objectives. We performed Sanger sequencing of PTPN11 hotspot (exons 3, 8, and 13). We report molecular analysis of 61 patients with NS phenotype belonging to 58 families. We screened for hotspot variants (exons 3, 8, and 13) in PTPN11 gene by Sanger sequencing. Twenty-seven patients were carrying heterozygous pathogenic variants of PTPN11 gene with a similar frequency (41.4%) compared to the literature. Our findings expand the variant spectrum of Moroccan patients with NS phenotype in whom the analysis of hotspot variants showed a high frequency of exons 3 and 8. This screening test allowed us to establish a molecular diagnosis in almost half of the patients with a good benefit-cost ratio, with appropriate management and genetic counseling.
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Síndrome de Noonan , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , alfa-Macroglobulinas , Humanos , Exones , Péptidos y Proteínas de Señalización Intracelular/genética , Mutación , Síndrome de Noonan/genética , Síndrome de Noonan/diagnóstico , Síndrome de Noonan/patología , Fenotipo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Proteínas Activadoras de ras GTPasa/genética , Proteínas Represoras/genética , Factores de Transcripción/genéticaRESUMEN
BACKGROUND: Congenital myasthenic syndromes (CMSs) are rare genetic diseases due to abnormalities of the neuromuscular junction leading to permanent or transient muscle fatigability and weakness. To date, 32 genes were found to be involved in CMSs with autosomal dominant and/or recessive inheritance patterns. CMS with acetylcholinesterase deficiency, in particular, was determined to be due to biallelic mutations of COLQ gene with early-onset clinical signs. Here, we report clinical features and novel molecular findings of COLQ-related CMS in a Moroccan patient with a review of the literature for this rare form. CASE PRESENTATION: In this study, we report the case of a 28-month-old Moroccan female patient with hypotonia, associated to axial muscle weakness, global motor delay, bilateral ptosis, unilateral partial visual field deficiency with normal ocular motility, and fatigable muscle weakness. Clinical exome sequencing revealed a novel homozygous deletion of exon 13 in COLQ gene, NM_005677.4(COLQ):c.(814+1_815-1)_(954+1_955-1) del p.(Gly272Aspfs*11). This finding was subsequently confirmed by quantitative real-time PCR (qPCR) in the proband and her parents. In silico analysis of protein-protein interaction network by STRING tool revealed that 12 proteins are highly associated to COLQ with an elevated confidence score. Treatment with Salbutamol resulted in clear benefits and recovery. CONCLUSIONS: This clinical observation illustrates the important place of next-generation sequencing in the precise molecular diagnosis of heterogeneous forms of CMS, the appropriate management and targeted treatment, and genetic counseling of families, with a better characterization of the mutational profile of this rare disease in the Moroccan population.
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Síndromes Miasténicos Congénitos , Acetilcolinesterasa/genética , Acetilcolinesterasa/metabolismo , Preescolar , Colágeno/genética , Colágeno/metabolismo , Variaciones en el Número de Copia de ADN , Femenino , Homocigoto , Humanos , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Debilidad Muscular , Mutación/genética , Síndromes Miasténicos Congénitos/genética , Eliminación de SecuenciaRESUMEN
BACKGROUND: Retinoblastoma (RB) is the most common malignant intraocular tumor in children; it affects their eyes often even prenatally. RB may be sporadic or familial, due to germinal mutation in RB1 gene or by abnormal chromosomal abnormalities involving RB1 gene, located in 13q14. Monosomy of subband 13q14 as a partial deletion can also be responsible for RB with additional symptoms. The latter may be RB associated with psychomotor retardation, macrocephaly, broad forehead, thick earlobes, and bulbous nose. MATERIALS AND METHODS: We present here the case of a boy from a consanguineous marriage with bilateral retinoblastoma, intellectual disability and facial dysmorphic features. Classical and molecular cytogenetics were used to recognize genotype-phenotype association. RESULTS: The karyotype showed a three way translocation involving chromosomes 5, 12 and 13. Further molecular cytogenetics analysis revealed a deletion of 13q14 involving the tumor suppressor gene RB1. CONCLUSION: This case highlights the impact of classical and molecular cytogenetics in diagnosis of rare genetic syndromes and for the genetic counselling of patients and their families. Pure molecular karyotyping analyses would miss the underlying chromosomal mechanism leading to the rearrangement.
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Discapacidad Intelectual , Neoplasias de la Retina , Retinoblastoma , Aberraciones Cromosómicas , Deleción Cromosómica , Genes de Retinoblastoma , Humanos , Discapacidad Intelectual/genética , Cariotipificación , Neoplasias de la Retina/genética , Retinoblastoma/genética , Retinoblastoma/patología , Translocación GenéticaRESUMEN
PURPOSE: Breast cancer (BC) is the most common form of female cancer around the world. BC is mostly sporadic, and rarely hereditary. These hereditary forms are mostly BRCA1- and BRCA2-associated hereditary breast and ovarian cancer syndrome. BRCA1 and BRCA2 genes are large and had some recurrent mutations specific to some populations. Through this work we analyze the most recurrent mutations in Moroccan population and compared them to a large review of other BRCA1/2 spectrum mutations in the MENA region. METHODS: We report in this work a series of 163 unrelated patients (the largest series of Moroccan patients) with familial breast and/or ovarian cancer, selected among patients referred to our oncogenetic outpatient clinic, from 2006 to 2021. To identify genetic variants in these two genes, different genetic analysis strategies have been carried out, using Sanger Sequencing DNA or Target Panel Sequencing. RESULTS: Pathogenic variants were identified in 27.6% of patients. The most frequent mutation identified in our patients was the c.1310_1313delAAGA, BRCA2 (33%), and three other mutations seem more frequent in the Moroccan population (33%) of all reported patients: c.798_799delTT, BRCA1; and c.3279delC, BRCA1; and c.7234_7235insG in BRCA2 gene. CONCLUSION: Through this work, we emphasize the importance of screening for BRCA1 and BRCA2 recurrent mutations in Moroccan patients. Other MENA (MENA: English-language acronym referring to the Middle East and North Africa region) countries had also some recurrent BRCA mutations, which will allow a fast and unexpensive first line genetic analysis and a precise molecular diagnosis. This will allow an adapted follow-up of the patients and a pre-symptomatic diagnosis of their relatives.
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Neoplasias de la Mama , Genes BRCA1 , Genes BRCA2 , Neoplasias Ováricas , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Femenino , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Mutación , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/genéticaRESUMEN
BACKGROUND: Rubinstein-Taybi syndrome (RSTS; OMIM 180849) is a rare autosomal dominant developmental disorder with an estimated prevalence of one case per 125,000 live births. RSTS is characterized by typical face, broad thumbs and halluces, short stature, and intellectual disability. Facial dysmorphy is characteristic with microcephaly, low frontal hairline, arched eyebrows, long eyelashes, convex profile of nose, narrow palate, and micrognathia. RSTS is mainly due to mutations or microdeletions of the CREBBP gene (about 60%) and more rarely of the EP300 gene (8%). OBJECTIVE: Clinical description and identification of mutations of patients with Rubinstein Taybi syndrome. METHODS: PCR and direct sequencing of CREBBP gene. RESULTS: We report here, the clinical and molecular data of a series of six Moroccan patients with a phenotype of RSTS. The molecular study of the major gene CREBBP (by Sanger Sequencing followed by CGH array, if sequence normal) revealed point mutations in five patients. For the sixth patient, CGH array revealed a microdeletion carrying the CREBBP gene. Through this work, we emphasize the importance of clinical expertise in the diagnosis, management and genetic counseling in Rubinstein Taybi syndrome.
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Mutación , Síndrome de Rubinstein-Taybi/genética , Síndrome de Rubinstein-Taybi/fisiopatología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Reacción en Cadena de la PolimerasaRESUMEN
Split-hand foot malformation (SHFM) is a clinically heterogeneous congenital limb defect affecting predominantly the central rays of hands and/or feet. The clinical expression varies in severity between patients as well between the limbs in the same individual. SHFM might be non-syndromic with limb-confined manifestations or syndromic with extra-limb manifestations. Isolated SHFM is a rare condition with an incidence of about 1 per 18,000 live born infants and accounts for 8-17 % of all limb malformations. To date, many chromosomal loci and genes have been described as associated with isolated SHFM, i.e., SHFM1 to 6. SHFM6 is one of the rarest forms of SHFM, and is caused by mutations in WNT10B gene. Less than ten pathogenic variants have been described. We have investigated a large consanguineous Moroccan family with three affected members showing feet malformations with or without split hand malformation phenotypes. Using an exome sequencing approach, we identified a homozygous nonsense variant p.Arg115* of WNT10B gene retaining thereby the diagnosis of SHFM6. This homozygous nonsense mutation identified by exome sequencing in a large family of split hand foot malformation highlights the importance of exome sequencing in genetically heterogeneous entities.
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Deformidades Congénitas de las Extremidades/diagnóstico , Proteínas Proto-Oncogénicas/genética , Proteínas Wnt/genética , Niño , Codón sin Sentido , Exoma/genética , Femenino , Homocigoto , Humanos , Deformidades Congénitas de las Extremidades/genética , Deformidades Congénitas de las Extremidades/fisiopatología , MarruecosRESUMEN
PURPOSE: Rare genetic variants in KDR, encoding the vascular endothelial growth factor receptor 2 (VEGFR2), have been reported in patients with tetralogy of Fallot (TOF). However, their role in disease causality and pathogenesis remains unclear. METHODS: We conducted exome sequencing in a familial case of TOF and large-scale genetic studies, including burden testing, in >1,500 patients with TOF. We studied gene-targeted mice and conducted cell-based assays to explore the role of KDR genetic variation in the etiology of TOF. RESULTS: Exome sequencing in a family with two siblings affected by TOF revealed biallelic missense variants in KDR. Studies in knock-in mice and in HEK 293T cells identified embryonic lethality for one variant when occurring in the homozygous state, and a significantly reduced VEGFR2 phosphorylation for both variants. Rare variant burden analysis conducted in a set of 1,569 patients of European descent with TOF identified a 46-fold enrichment of protein-truncating variants (PTVs) in TOF cases compared to controls (P = 7 × 10-11). CONCLUSION: Rare KDR variants, in particular PTVs, strongly associate with TOF, likely in the setting of different inheritance patterns. Supported by genetic and in vivo and in vitro functional analysis, we propose loss-of-function of VEGFR2 as one of the mechanisms involved in the pathogenesis of TOF.
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Tetralogía de Fallot , Receptor 2 de Factores de Crecimiento Endotelial Vascular , Animales , Predisposición Genética a la Enfermedad , Células HEK293 , Humanos , Ratones , Tetralogía de Fallot/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Secuenciación del ExomaRESUMEN
BACKGROUND: Merosin-deficient congenital muscular dystrophy type 1A (MDC1A) is a rare autosomal recessive genetic condition caused by deleterious mutations in the LAMA2 gene encoding the laminin-α2 chain. It is the most frequent subtype of congenital muscular dystrophies (CMDs) characterized by total laminin-α2 deficiency with muscle weakness at birth or in the first six months of life. To the best of our knowledge, this study reports the first molecular diagnosis and genetic defect of this heterogeneous form of CMD performed in a Moroccan medical genetic center using next-generation sequencing (NGS). It allows us to expand the mutational spectrum of the LAMA2 gene. CASE PRESENTATION: We report the case of a female Moroccan child with clinical and paraclinical features in favor of a CMD. She has global congenital hypotonia with generalized muscle weakness, psychomotor retardation, increased serum creatine kinase, and normal brain scan at the age of six months. Targeted NGS leads to the identification of a novel homozygous nonsense mutation c.2217G > A, p.(Trp739*) in the exon 16 of LAMA2. Sanger sequencing confirmed this mutation in the affected patient and showed that her parents are heterozygous carriers. CONCLUSIONS: A modern genetic analysis by NGS improves the genetic diagnosis pathway for adequate genetic counseling of affected families more precisely. An accession number from the National Center for Biotechnology Information (NCBI) ClinVar database was retrieved for this novel LAMA2 mutation.
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Distrofias MuscularesRESUMEN
Dystrophinopathies are the most common genetic neuromuscular disorders during childhood, with an X-linked recessive inheritance pattern. Because of clinical and genetic heterogeneity of dystrophinopathies, genetic testing of dystrophin gene at Xp21.2 is constantly evolving. Multiplex Polymerase Chain Reaction (MPCR) is used in the first line to detect common exon deletions of dystrophin gene (accounting for 65% of mutations), followed by the Multiplex Ligation-dependent Probe Amplification (MLPA) technique to reveal deletions of exons outside the usual hotspot and duplications in male and female carriers. (MLPA adds another 10-15% positive cases to MPCR). Recently, Next Generation Sequencing allows to screen for rare large and point mutations. We report here, molecular analysis results of dystrophin gene during 27 years in a large Moroccan cohort of 356 patients, using the multiplex polymerase chain reaction (MPCR) to screen for hot-spot exon deletions. First applications of whole dystrophin gene sequencing in our lab lead to the identification of six novel mutations.
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Distrofina/genética , Distrofia Muscular de Duchenne/genética , Mutación , Adolescente , Adulto , Niño , Preescolar , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Marruecos , Reacción en Cadena de la Polimerasa Multiplex , Distrofia Muscular de Duchenne/diagnóstico , Adulto JovenRESUMEN
A failure in optic fissure fusion during development can lead to blinding malformations of the eye. Here, we report a syndrome characterized by facial dysmorphism, colobomatous microphthalmia, ptosis and syndactyly with or without nephropathy, associated with homozygous frameshift mutations in FAT1. We show that Fat1 knockout mice and zebrafish embryos homozygous for truncating fat1a mutations exhibit completely penetrant coloboma, recapitulating the most consistent developmental defect observed in affected individuals. In human retinal pigment epithelium (RPE) cells, the primary site for the fusion of optic fissure margins, FAT1 is localized at earliest cell-cell junctions, consistent with a role in facilitating optic fissure fusion during vertebrate eye development. Our findings establish FAT1 as a gene with pleiotropic effects in human, in that frameshift mutations cause a severe multi-system disorder whereas recessive missense mutations had been previously associated with isolated glomerulotubular nephropathy.
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Blefaroptosis/genética , Cadherinas/genética , Coloboma/genética , Enfermedades Renales/genética , Microftalmía/genética , Organogénesis/genética , Sindactilia/genética , Adolescente , Adulto , Animales , Células Cultivadas , Niño , Preescolar , Análisis Mutacional de ADN , Embrión de Mamíferos , Ojo/embriología , Huesos Faciales/anomalías , Femenino , Mutación del Sistema de Lectura , Humanos , Uniones Intercelulares/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Cultivo Primario de Células , Epitelio Pigmentado de la Retina/citología , Síndrome , Secuenciación del Exoma , Adulto Joven , Pez Cebra , Proteínas de Pez Cebra/genéticaRESUMEN
BACKGROUND: Pompe disease is an autosomal recessive lysosomal storage disorder characterized by progressive myopathy with proximal muscle weakness, respiratory muscle dysfunction, and cardiomyopathy. Its prevalence ranges between 1/9000 and 1/40,000. It is caused by compound heterozygous or homozygous mutations in the GAA gene, which encodes for the lysosomal enzyme alpha-glucosidase, required for the degrading of lysosomal glycogen. CASE PRESENTATION: In this study, we report the case of a Moroccan consanguineous family with hypertrophic cardiomyopathy and sudden cardiac deaths at an early age; our patient was a 7-month-old Moroccan girl. Whole exome sequencing identified the deleterious homozygous mutation c.236_246delCCACACAGTGC (p.Pro79ArgfsX13) of GAA gene leading to a post-mortem diagnosis of Pompe disease. CONCLUSION: The identification of the genetic substrate in our patient, the daughter, confirmed the clinical diagnosis of Pompe disease and allowed us to provide appropriate genetic counseling to the family for future pregnancies.
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Secuenciación del Exoma , Exoma/genética , Enfermedad del Almacenamiento de Glucógeno Tipo II/diagnóstico , Enfermedad del Almacenamiento de Glucógeno Tipo II/genética , Autopsia , Cardiomiopatía Hipertrófica/diagnóstico , Cardiomiopatía Hipertrófica/genética , Muerte Súbita/etiología , Muerte Súbita/patología , Femenino , Asesoramiento Genético , Predisposición Genética a la Enfermedad , Humanos , Lactante , Marruecos , alfa-GlucosidasasRESUMEN
One of the author's name on this article was incorrectly spelled as "Renata Borcciadi". The correct spelling is "Renata Bocciardi" and is now presented correctly in this article.
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The objective of this study was to report the clinical and biological characteristics of two Perrault syndrome cases in a Moroccan family with homozygous variant c.1565C>A in the LARS2 gene and to establish genotype-phenotype correlation of patients with the same mutation by review of the literature. Whole-exome sequencing was performed. Data analysis was carried out and confirmed by Sanger sequencing and segregation. The affected siblings were diagnosed as having Perrault syndrome with sensorineural hearing loss at low frequencies; the female proband had primary amenorrhea and ovarian dysgenesis. Both affected individuals had a marfanoid habitus and no neurological features. Both patients carried the homozygous variant c.1565C>A; p.Thr522Asn in exon 13 of the LARS2 gene. This variant has already been reported as a homozygous variant in three other Perrault syndrome families. Both affected siblings of a Moroccan consanguineous family with LARS2 variants had low-frequency sensorineural hearing loss, marfanoid habitus, and primary ovarian insufficiency in the affected girl. According to the literature, this variant, c.1565C>A; p.Thr522Asn, can be correlated with low-frequency hearing loss. However, marfanoid habitus was been considered a nonspecific feature in Perrault syndrome, but we believe that it may be more specific than considered previously. This diagnosis allowed us to provide appropriate management to the patients and to provide more accurate genetic counseling to this family.
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Disgenesia Gonadal 46 XX/complicaciones , Pérdida Auditiva Sensorineural/complicaciones , Síndrome de Marfan/complicaciones , Adolescente , Secuencia de Aminoácidos , Aminoacil-ARNt Sintetasas/química , Aminoacil-ARNt Sintetasas/genética , Secuencia de Bases , Femenino , Genotipo , Disgenesia Gonadal 46 XX/genética , Pérdida Auditiva Sensorineural/genética , Humanos , Masculino , Síndrome de Marfan/genética , Linaje , Fenotipo , Reproducibilidad de los Resultados , Secuenciación del Exoma , Adulto JovenRESUMEN
BACKGROUND: To date, a limited number of BRCA1/2 germline mutations have been reported in hereditary breast and/or ovarian cancer in the Moroccan population. Less than 20 different mutations of these two genes have been identified in Moroccan patients, and recently we reported a further BRCA2 mutation (c.1310_1313delAAGA; p.Lys437IlefsX22) in three unrelated patients, all from the North-East of the country. We aimed in this study to evaluate the frequency and geographic distribution of this BRCA2 frameshift mutation, in order to access its use as the first-line BRCA genetic testing strategy for Moroccan patients. We enrolled in this study 122 patients from different regions of Morocco, with suggestive inherited predisposition to breast and ovarian cancers. All subjects gave written informed consent to BRCA1/2 genetic testing. According to available resources of our lab and enrolled families, 51 patients were analyzed by the conventional individual exon-by-exon Sanger sequencing, 23 patients were able to benefit from a BRCA next generation sequencing and a target screening for exon 10 of BRCA2 gene was performed in 48 patients. RESULTS: Overall, and among the 122 patients analyzed for at least the exon 10 of the BRCA2 gene, the c.1310_1313delAAGA frameshift mutation was found in 14 patients. Genealogic investigation revealed that all carriers of this mutation shared the same geographic origin and were descendants of the North-East of Morocco. DISCUSSION: In this study, we highlighted that c.1310_1313delAAGA mutation of BRCA2 gene is recurrent with high frequency in patients from the North-East region of Morocco. Therefore, we propose to use, in public health strategies, the detection of this mutation as the first-line screening tests in patients with breast and ovarian cancer originated from this region.