RESUMEN
Recurrent miscarriage (RM) affects millions of couples globally, and half of them have no demonstrated etiology. Genome sequencing (GS) is an enhanced and novel cytogenetic tool to define the contribution of chromosomal abnormalities in human diseases. In this study we evaluated its utility in RM-affected couples. We performed low-pass GS retrospectively for 1,090 RM-affected couples, all of whom had routine chromosome analysis. A customized sequencing and interpretation pipeline was developed to identify chromosomal rearrangements and deletions/duplications with confirmation by fluorescence in situ hybridization, chromosomal microarray analysis, and PCR studies. Low-pass GS yielded results in 1,077 of 1,090 couples (98.8%) and detected 127 chromosomal abnormalities in 11.7% (126/1,077) of couples; both members of one couple were identified with inversions. Of the 126 couples, 39.7% (50/126) had received former diagnostic results by karyotyping characteristic of normal human male or female karyotypes. Low-pass GS revealed additional chromosomal abnormalities in 50 (4.0%) couples, including eight with balanced translocations and 42 inversions. Follow-up studies of these couples showed a higher miscarriage/fetal-anomaly rate of 5/10 (50%) compared to 21/93 (22.6%) in couples with normal GS, resulting in a relative risk of 2.2 (95% confidence interval, 1.1 to 4.6). In these couples, this protocol significantly increased the diagnostic yield of chromosomal abnormalities per couple (11.7%) in comparison to chromosome analysis (8.0%, chi-square test p = 0.000751). In summary, low-pass GS identified underlying chromosomal aberrations in 1 in 9 RM-affected couples, enabling identification of a subgroup of couples with increased risk of subsequent miscarriage who would benefit from a personalized intervention.
Asunto(s)
Aborto Habitual/diagnóstico , Aborto Habitual/genética , Aberraciones Cromosómicas , Secuenciación Completa del Genoma/métodos , Adulto , Femenino , Estudios de Seguimiento , Humanos , Cariotipificación , Masculino , Embarazo , Pronóstico , Estudios RetrospectivosRESUMEN
We present a comprehensive clinically oriented workflow for large-insert genome sequencing (liGS)-based nucleotide level resolution and interpretation of de novo (dn) apparently balanced chromosomal abnormalities (BCA) in prenatal diagnosis (PND). Retrospective or concomitant with conventional PND and liGS, molecular and newly developed clinically inspired bioinformatic tools (TAD-GConTool and CNV-ConTool) are applied to analyze and assess the functional and phenotypic outcome of dn structural variants (dnSVs). Retrospective analysis of four phenotype-associated dnSVs identified during conventional PND precisely reveal the genomic elements disrupted by the translocation breakpoints. Identification of autosomal dominant disease due to the disruption of ANKS1B and WDR26 by t(12;17)(q23.1;q21.33)dn and t(1;3)(q24.11;p25.3)dn breakpoints, respectively, substantiated the proposed workflow. We then applied this workflow to two ongoing prenatal cases with apparently balanced dnBCAs: 46,XX,t(16;17)(q24;q21.3)dn referred for increased risk on combined first trimester screening and 46,XY,t(2;19)(p13;q13.1)dn referred due to a previous trisomy 21 pregnancy. Translocation breakpoints in the t(16;17) involve ANKRD11 and WNT3 and disruption of ANKRD11 resulted in KBG syndrome confirmed in postnatal follow-up. Breakpoints in the t(2;19) are within ATP6V1B1 and the 3' UTR of CEP89, and are not interpreted to cause disease. Genotype-phenotype correlation confirms the causative role of WDR26 in the Skraban-Deardorff and 1q41q42 microdeletion phenocopy syndromes, and that disruption of ANKS1B causes ANKS1B haploinsufficiency syndrome. In sum, we show that an liGS-based approach can be realized in PND care providing additional information concerning clinical outcomes of dnBCAs in patients with such rearrangements.
Asunto(s)
Anomalías Múltiples , Enfermedades del Desarrollo Óseo , Trastornos de los Cromosomas , Cromosomas Humanos/genética , Facies , Genes Dominantes , Discapacidad Intelectual , Diagnóstico Prenatal , Anomalías Dentarias , Translocación Genética , Anomalías Múltiples/diagnóstico , Anomalías Múltiples/genética , Adolescente , Adulto , Enfermedades del Desarrollo Óseo/diagnóstico , Enfermedades del Desarrollo Óseo/genética , Trastornos de los Cromosomas/diagnóstico , Trastornos de los Cromosomas/genética , Femenino , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Masculino , Embarazo , Anomalías Dentarias/diagnóstico , Anomalías Dentarias/genética , Flujo de TrabajoRESUMEN
Oocyte maturation defect is a challenging situation in the management of infertility, the etiology may be related to endocrine causes, protocols used in ovarian stimulation, oocyte intrinsic defects or procedures in embryology laboratory. We report three Mexican females in treatment for primary infertility with non-mature oocytes after ovary stimulation and oocyte capture in whom a genetic diagnosis of TUBB8-oocyte maturation defect was revealed by exome sequencing. Two couples achieved pregnancies though oocyte donation after establishing the genetic etiology. Our results expand the role of TUBB8-disorders in patients of non-Asian ethnicity. Oocyte maturation defects of monogenic origin are a growing group of disorders that endocrinologists and reproductive medicine specialists should be aware in order to provide referral to genetics for establish a correct and opportune diagnosis.
Asunto(s)
Enfermedades Genéticas Congénitas/terapia , Infertilidad Femenina/diagnóstico , Infertilidad Femenina/terapia , Oogénesis/genética , Tubulina (Proteína)/genética , Adulto , Análisis Mutacional de ADN , Femenino , Enfermedades Genéticas Congénitas/diagnóstico , Enfermedades Genéticas Congénitas/epidemiología , Humanos , Infertilidad Femenina/epidemiología , Infertilidad Femenina/genética , México , Mutación , Linaje , Embarazo , Pronóstico , Técnicas Reproductivas Asistidas/estadística & datos numéricos , Resultado del TratamientoRESUMEN
PURPOSE: There is little long-term, population-based data on uptake of prenatal diagnosis for Huntington disease (HD), a late-onset autosomal dominant neurodegenerative disorder, and the effect of the availability of preimplantation genetic diagnosis (PGD) on families' decisions about conventional prenatal diagnosis is not known. We report trends in prenatal diagnosis and preimplantation diagnosis for HD in the United Kingdom since services commenced. METHODS: Long-term UK-wide prospective case record-based service evaluation in 23 UK Regional Genetic Centres 1988-2015, and four UK PGD centers 2002-2015. RESULTS: From 1988 to 2015, 479 prenatal diagnoses were performed in the UK for HD. An exclusion approach was used in 150 (31%). The annual rate of HD prenatal diagnosis has remained around 18 (3.5/million) over 27 years, despite a steady increase in the use of PGD for HD since 2002. CONCLUSION: Although increasing number of couples are choosing either direct or exclusion PGD to prevent HD in their offspring, both direct and exclusion prenatal diagnosis remain important options in a health system where both PGD and prenatal diagnosis are state funded. At-risk couples should be informed of all options available to them, preferably prepregnancy.
Asunto(s)
Enfermedad de Huntington/diagnóstico , Diagnóstico Prenatal , Femenino , Humanos , Masculino , Embarazo , Diagnóstico Preimplantación , Estudios Prospectivos , Reino UnidoRESUMEN
Werner syndrome (WS) is a rare autosomal recessive disorder characterized by a constellation of adult onset phenotypes consistent with an acceleration of intrinsic biological aging. It is caused by pathogenic variants in the WRN gene, which encodes a multifunctional nuclear protein with exonuclease and helicase activities. WRN protein is thought to be involved in optimization of various aspects of DNA metabolism, including DNA repair, recombination, replication, and transcription. In this update, we summarize a total of 83 different WRN mutations, including eight previously unpublished mutations identified by the International Registry of Werner Syndrome (Seattle, WA) and the Japanese Werner Consortium (Chiba, Japan), as well as 75 mutations already reported in the literature. The Seattle International Registry recruits patients from all over the world to investigate genetic causes of a wide variety of progeroid syndromes in order to contribute to the knowledge of basic mechanisms of human aging. Given the unusually high prevalence of WS patients and heterozygous carriers in Japan, the major goal of the Japanese Consortium is to develop effective therapies and to establish management guidelines for WS patients in Japan and elsewhere. This review will also discuss potential translational approaches to this disorder, including those currently under investigation.
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Mutación , Helicasa del Síndrome de Werner/genética , Síndrome de Werner/genética , Factores de Edad , Animales , Bases de Datos Genéticas , Modelos Animales de Enfermedad , Exones , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Geografía , Humanos , Japón , Ratones , Fenotipo , Polimorfismo Genético , Polimorfismo de Nucleótido Simple , Sistema de Registros , Investigación Biomédica Traslacional , Navegador Web , Síndrome de Werner/diagnóstico , Síndrome de Werner/epidemiologíaRESUMEN
Nasopalpebral lipoma-coloboma syndrome (NPLCS, OMIM%167730) is an uncommon malformation entity with autosomal dominant inheritance characterized by the combination of nasopalpebral lipoma, colobomas in upper and lower eyelids, telecanthus, and maxillary hypoplasia. To date, no genetic defects have been associated with familial or sporadic NPLCS cases and the etiology of the disease remains unknown. In this work, the results of whole exome sequencing in a sporadic NPLCS patient are presented. Exome sequencing identified a de novo heterozygous frameshift dinucleotide insertion c.6245_6246 insTT (p.His2082fs*67) in ZDBF2 (zinc finger, DBF-type containing 2), a gene located at 2q33.3. This variant was absent in parental DNA, in a set of 300 ethnically matched controls, and in public exome variant databases. This is the first genetic variant identified in a NPLCS patient and evidence supporting the pathogenicity of the identified mutation is discussed. © 2016 Wiley Periodicals, Inc.
Asunto(s)
Anomalías Múltiples/genética , Secuencia de Bases/genética , Coloboma/genética , Proteínas de Unión al ADN/genética , Neoplasias de los Párpados/genética , Impresión Genómica , Lipoma/genética , Anomalías Múltiples/fisiopatología , Preescolar , Coloboma/fisiopatología , Exoma/genética , Neoplasias de los Párpados/fisiopatología , Femenino , Mutación del Sistema de Lectura , Humanos , Lipoma/fisiopatología , LinajeRESUMEN
We report on an adult male with normal intelligence who exhibited an unusual combination of microcephaly, dysostoses of limbs, vertebrae, patellae, and pubic bone, camptodactyly of all fingers, and syndactyly of toes, absent nails on thumbs and some fingers, bilateral cataract, cryptorchidism, polythelia, and nipple-like skin pigmentations of shoulders and upper back. We have been unable to find a description of a similar combination of manifestations in literature. The cause of the anomalies remains unknown.
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Catarata/diagnóstico , Disostosis/diagnóstico , Microcefalia/diagnóstico , Anomalías Múltiples , Adulto , Huesos/diagnóstico por imagen , Huesos/patología , Bandeo Cromosómico , Variaciones en el Número de Copia de ADN , Genómica , Humanos , Imagenología Tridimensional , Masculino , Fenotipo , Polimorfismo de Nucleótido Simple , Síndrome , Tomografía Computarizada por Rayos XRESUMEN
Nasopalpebral lipoma-coloboma syndrome is an extremely uncommon autosomal dominant condition characterized by congenital upper eyelid and nasopalpebral lipomas, colobomata of upper and lower eyelids, telecanthus, and maxillary hypoplasia. A few familial and sporadic cases of this malformation syndrome have been previously reported. Here, the clinical, radiological, and histopathological features of a sporadic Mexican patient with the nasopalpebral lipoma-coloboma syndrome are described. To our knowledge, this is the first time that craniofacial 3D computed tomography imaging was used for a detailed assessment of the facial lipoma.
Asunto(s)
Anomalías Múltiples/diagnóstico por imagen , Coloboma/diagnóstico por imagen , Neoplasias de los Párpados/diagnóstico por imagen , Hamartoma/diagnóstico por imagen , Lipoma/diagnóstico por imagen , Tumor de Músculo Liso/diagnóstico por imagen , Anomalías Múltiples/patología , Coloboma/patología , Neoplasias de los Párpados/patología , Párpados/anomalías , Párpados/diagnóstico por imagen , Femenino , Hamartoma/patología , Humanos , Lactante , Cariotipificación , Lipoma/patología , Radiografía , Tumor de Músculo Liso/patologíaRESUMEN
AIM: To analyze the presence of Y chromosome microdeletions in males of Mexican couples with idiopathic recurrent pregnancy losses (RPL). METHODS: Seventy-one males from couples with RPL and 66 fertile males as controls were studied. DNA was isolated from peripheral lymphocytes and used to run multiplex polymerase chain reactions. Regions AZFa (sY84, sY86), AZFb (sY127, sY134) and AZFc (sY254, sY255) of the Y chromosome were analyzed according to valid guidelines recommended by the European Academy of Andrology and the European Molecular Genetics Quality Network. Also, the sequence tagged sites (STSs): DYS262 (sY67), DYS220 (sY129), DYF85S1 (sY150), DYF86S1 (sY152) and DYF87S1 (sY153) were included in order to analyze STSs previously reported as deleted. A power analysis to support our simple size was performed. RESULTS: Results show an absence of Y chromosome microdeletions in males of couples with RPL and controls with an acceptable statistical power. CONCLUSION: The study did not show an association of recurrent pregnancy loss and Y chromosome microdeletions in Mexican male partners. Based on the results, the study of Y chromosome microdeletions in couples with RPL is not considered clinically relevant.
Asunto(s)
Aborto Habitual/etiología , Trastornos de los Cromosomas Sexuales del Desarrollo Sexual/fisiopatología , Adulto , Deleción Cromosómica , Cromosomas Humanos Y/genética , Composición Familiar , Femenino , Pruebas Genéticas , Humanos , Infertilidad Masculina , Masculino , México , Persona de Mediana Edad , Embarazo , Aberraciones Cromosómicas Sexuales , Trastornos de los Cromosomas Sexuales del Desarrollo Sexual/diagnóstico , Trastornos de los Cromosomas Sexuales del Desarrollo Sexual/genética , Adulto JovenRESUMEN
Despite numerous clinical series, consistent karyotype-phenotype correlations for Turner syndrome have not been established, although a lower level of 45,X is generally thought to be associated with a milder phenotype. This limits personalized counseling for women with 45,X/46,XX mosaicism. To better understand the phenotypic spectrum associated with various levels of 45,X/46,XX mosaicism, we compared patients evaluated in the Massachusetts General Hospital Turner Syndrome Clinic to determine if cardiac, renal, and thyroid abnormalities correlated with the percentage of 45,X cells present in a peripheral blood karyotype. of the 118 patients included in the study, 78 (66%) patients had non-mosaic 45,X and 40 (34%) patients had varying levels of 45,X/46,XX mosaicism. Patients with ≤70% 45,X compared with those with >70% 45,X had a significantly lower frequency of cardiac and renal anomalies. The presence of hypothyroidism was somewhat lower for the ≤70% 45,X group, but was not statistically significant. Supplemental tissue testing on another tissue type, typically buccal mucosa, was often useful in counseling patients with 45,X mosaicism. Given the modest sample size of patients with varying levels of mosaicism and the variability of Turner syndrome abnormalities, we hope this preliminary study will inspire a multicenter collaboration, which may lead to modification of clinical guidelines. Because several patients with ≤70% 45,X were ascertained from perinatal care referrals, we still advise women with 45,X mosaicism pursuing pregnancy to receive standard Turner syndrome cardiac surveillance. There is an opportunity to personalize counseling and surveillance for patients based on percentage of 45,X cells on chromosome analysis.
Asunto(s)
Trastornos del Desarrollo Sexual 46, XX/genética , Pruebas Genéticas/métodos , Cariotipificación/métodos , Mosaicismo , Fenotipo , Medicina de Precisión/métodos , Síndrome de Turner/genética , Trastornos del Desarrollo Sexual 46, XX/diagnóstico , Células Cultivadas , Femenino , Pruebas Genéticas/normas , Humanos , Cariotipificación/normas , Medicina de Precisión/normas , Síndrome de Turner/diagnósticoRESUMEN
Novel cytogenetic tools are increasingly based on genome sequencing for detecting chromosomal abnormalities. Different sequence-based techniques optimized for diagnosis of structural variants can be useful for narrowing down the localization of breakpoints of chromosomal abnormalities, but do not offer nucleotide resolution of breakpoints for proper interpretation of gene disruption. This protocol presents the characterization of structural variants at nucleotide resolution using Sanger sequencing after low-pass large-insert genome sequencing or other long-molecule methods. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Primer design for junction amplification at translocations and inversions Basic Protocol 2: Amplification of derivative chromosomes using a long-range polymerase Alternate Protocol: Amplification of derivative chromosomes using a hot-start polymerase Basic Protocol 3: Preparation of DNA for Sanger sequencing Basic Protocol 4: Interpretation and reporting of breakpoints based on Sanger sequencing.
Asunto(s)
Aberraciones Cromosómicas , Puntos de Rotura del Cromosoma , Reordenamiento Génico/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Nucleótidos/genética , Translocación Genética/genética , Secuencia de Bases , Mapeo Cromosómico/métodos , ADN/análisis , ADN/genética , ADN/aislamiento & purificación , Cartilla de ADN/genética , Electroforesis en Gel de Agar/métodos , Humanos , Reacción en Cadena de la Polimerasa/métodos , Programas InformáticosRESUMEN
OBJECTIVE: In this study, we report an experience of 59 natural-cycle IVF combined with in vitro oocyte maturation (IVF/M) cycles in patients with PCOS requiring IVF recruited based on limitations to afford a conventional IVF treatment in a 9-years period. Results of IVF/M were compared with 164 cycles of IVF in PCOS patients. MATERIAL AND METHODS: In IVF/M cycles only hCG priming was used before oocyte recovery, with in vitro maturation of immature oocytes in a commercial medium. In conventional IVF group, recombinant FSH (rFSH) and GnRH agonist/antagonist for ovarian stimulation were used. In both groups, fertilization was achieved by intracytoplasmic sperm injection (ICSI) of mature oocytes and fresh embryos transferred at day 2 or day 3. RESULTS: In all IVF/M cycles oocytes and transferable quality embryos were obtained, only in 6 IVF/M cycles mature oocytes were obtained at oocyte capture day. Clinical pregnancy rate per cycle was 39.0% vs 53.6% (p = 0.0682) and delivery rate per cycle was 30.5% vs 42.6% (p = 0.1209) in IVF/M and conventional IVF respectively. Patients with ovarian hyperstimulation syndrome (OHSS) were 0% in IVF/M vs 6.7% in conventional IVF (p = 0.0399). CONCLUSION: Our experience in a private clinic in Mexico suggests that IVF/M can be a useful initial strategy to treat PCOS patients requiring IVF with comparable delivery rates to conventional IVF and a decreased risk of ovary hyperstimulation. IVF/M may be indicated to patients with limited resources paying without insurance for their infertility treatment.
Asunto(s)
Fertilización In Vitro/métodos , Técnicas de Maduración In Vitro de los Oocitos/métodos , Infertilidad Femenina/terapia , Adulto , Femenino , Humanos , Técnicas de Maduración In Vitro de los Oocitos/economía , Infertilidad Femenina/etiología , Recuperación del Oocito/métodos , Inducción de la Ovulación/métodos , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/diagnóstico , Embarazo , Índice de Embarazo , Adulto JovenRESUMEN
Background: Pediatric movement disorders represent a diagnostic challenge for pediatricians and pediatric neurologists due to their high clinical heterogeneity and shared common features. Therefore, specific diagnoses require different approaches including metabolic work-up and specific tests for frequent genetic conditions. Alternating hemiplegia of childhood (AHC) is an ultra-rare pediatric movement disorder, characterized by paroxysmal alternating hemiplegia, dystonia, and seizure-like episodes that can be misleading during the evaluation of a child with a movement disorder. Case report: We present a Mexican patient with abnormal movements referred to the Genetics clinic because of hyperammonemia and a possible organic acidemia. Our assessment did not find clinical features compatible with an inborn error of metabolism. A massively parallel sequencing approach with targeted panel sequencing was used to get a final diagnosis. A missense variant c.2839G>A (p.Gly947Arg) located at exon 21 of ATP1A3 gene was demonstrated. This variant (rs398122887) has been previously reported as de novo producing alternating hemiplegia of childhood (AHC). Conclusions: AHC is an ultra-rare syndrome presented as a movement disorder with seizure-like episodes and a unique facial phenotype. Clinicians should be aware of this combination in order to diagnose this condition in a timely manner. Massive parallel sequencing panels are emerging as the best approach to diagnose rare movement disorders and simultaneously rule out metabolic disorders and common epileptic syndromes.
Introducción: Los trastornos pediátricos del movimiento representan un reto diagnóstico para pediatras y neurólogos pediatras debido a su gran heterogeneidad clínica y características comunes compartidas. Por lo tanto, los diagnósticos específicos requieren de diferentes abordajes que incluyen la búsqueda de desórdenes metabólicos y pruebas específicas para condiciones genéticas frecuentes. La hemiplejia alternante de la infancia (AHC) es un trastorno pediátrico del movimiento poco común, caracterizado por cuadros paroxísticos de hemiplejia alternante, distonía y episodios semejantes a crisis epilépticas, que pueden resultar desorientadores durante el abordaje diagnóstico de un infante con un desorden del movimiento. Caso clínico: Presentamos una paciente mexicana con movimientos anormales referida a la Clínica de Genética por hiperamonemia y una posible acidemia orgánica. Nuestro abordaje no identificó características clínicas compatibles con un error innato del metabolismo. Se utilizó un abordaje basado en secuenciación masiva en paralelo para obtener un diagnóstico final. Se demostró una variante de sentido equivocado c.2839G>A (p.Gly947Arg) localizada en el exón 21 del gen ATP1A3. Esta variante (rs398122887) ha sido previamente reportada como de novo, ocasionando AHC. Conclusiones: La AHC es un síndrome excepcionalmente raro que se presenta con un trastorno del movimiento con cuadros semejantes a crisis epilépticas y un fenotipo facial particular. Los médicos deben ser conscientes de esta combinación con el fin de diagnosticar oportunamente esta condición. Los paneles de secuenciación masiva están emergiendo como el mejor abordaje para diagnosticar trastornos del movimiento raros y, simultáneamente, descartar trastornos metabólicos y síndromes epilépticos comunes.
Asunto(s)
Hemiplejía/diagnóstico , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , ATPasa Intercambiadora de Sodio-Potasio/genética , Preescolar , Femenino , Hemiplejía/genética , Hemiplejía/fisiopatología , Humanos , México , MutaciónRESUMEN
Introducción: Los errores innatos en la síntesis de ácidos biliares son un grupo de defectos genéticos que representan del 1 al 2% de las enfermedades colestásicas crónicas en lactantes, niños y adolescentes. La deficiencia de 3b-Δ5-C27-hidroxiesteroide oxidoreductasa (3b-HSDH) es el defecto más comúnmente reportado. El cuadro clínico característico consiste en hepatitis neonatal, hepatomegalia, esplenomegalia, malabsorción, desnutrición y enfermedad hepática de aparición tardía. Caso clínico: Lactante masculino con antecedente de ictericia en escleras a los 4 meses que se resolvió espontáneamente; posteriormente, a los 18 meses, presentó enfermedad colestásica. Durante su abordaje se documentó gamma-glutamil transpeptidasa normal, hallazgo que es altamente sugestivo de alteración en la síntesis de ácidos biliares. El diagnóstico se realizó con espectrometría de masas en orina. Se inició tratamiento con ácido cólico oral, y presentó mejoría inmediata. Conclusiones: El resultado en los ácidos biliares urinarios es definitivo para el defecto genético y consistente con mutaciones homocigotas en el gen HSD3B7. Este padecimiento constituye un diagnóstico de exclusión en las enfermedades colestásicas de la infancia, particularmente el hallazgo de gamma-glutamil transpeptidasa normal o levemente aumentada, y responde adecuadamente al tratamiento oral, por lo que debe identificarse de forma temprana. Background: Inborn errors in bile acid synthesis are a group of genetic defects accounting for 1 to 2% of chronic cholestatic diseases in infants, children and adolescents. Deficiency of 3b-Δ5-C27-hydroxysteroid dehydrogenase (3ß-HSDH) is the most common defect in this disease. Clinical features consist of neonatal hepatitis, hepatomegaly, splenomegaly, malabsorption, malnutrition, and late-onset liver disease. Case report: A male infant who presented jaundice in sclera at 4 months that resolved spontaneously, later presented cholestatic disease at 18 months. During his approach, normal gamma-glutamyl transpeptidase was documented, a finding that is highly suggestive of alteration in the synthesis of bile acids. The diagnosis was made using urine mass spectrometry. Oral colic acid treatment was started, presenting immediate improvement. Conclusions: The result in urinary bile acids is definitive for the genetic defect and consistent with homozygous mutations in the HSD3B7 gene. This condition is a diagnosis of exclusion in childhood cholestatic diseases, particularly in the presence of normal or mildly enlarged gamma-glutamyl transpeptidase, and responds adequately to oral treatment; it should be identified early.
Asunto(s)
3-Hidroxiesteroide Deshidrogenasas/genética , Ácidos y Sales Biliares/metabolismo , Colestasis/diagnóstico , Errores Innatos del Metabolismo/diagnóstico , Colestasis/genética , Ácido Cólico/administración & dosificación , Humanos , Lactante , Ictericia/etiología , Masculino , Errores Innatos del Metabolismo/genéticaRESUMEN
Lysosomal acid lipase (LAL) deficiency is an under-recognized lysosomal disease caused by deficient enzymatic activity of LAL. In this report we describe two affected female Mexican siblings with early hepatic complications. At two months of age, the first sibling presented with alternating episodes of diarrhea and constipation, and later with hepatomegaly, elevated transaminases, high levels of total and low-density lipoprotein cholesterol, and low levels of high-density lipoprotein. Portal hypertension and grade 2 esophageal varices were detected at four years of age. The second sibling presented with hepatomegaly, elevated transaminases and mildly elevated low-density lipoprotein and low high-density lipoprotein at six months of age. LAL activity was deficient in both patients. Sequencing of LIPA revealed two previously unreported heterozygous mutations in exon 4: c.253C>A and c.294C>G. These cases highlight the clinical continuum between the so-called Wolman disease and cholesteryl ester storage disease, and underscore that LAL deficiency represents a single disease with a degree of clinical heterogeneity.
Asunto(s)
Mutación , Hermanos , Esterol Esterasa/deficiencia , Esterol Esterasa/genética , Enfermedad de Wolman/genética , Biopsia , Niño , Preescolar , Análisis Mutacional de ADN , Progresión de la Enfermedad , Várices Esofágicas y Gástricas/enzimología , Várices Esofágicas y Gástricas/genética , Esofagoscopía , Exones , Hígado Graso/enzimología , Hígado Graso/genética , Femenino , Predisposición Genética a la Enfermedad , Hepatomegalia/enzimología , Hepatomegalia/genética , Heterocigoto , Humanos , Hipertensión Portal/enzimología , Hipertensión Portal/genética , Inmunohistoquímica , Lactante , Cirrosis Hepática/enzimología , Cirrosis Hepática/genética , México , Linaje , Fenotipo , Hermanos/etnología , Factores de Tiempo , Ultrasonografía Doppler en Color , Enfermedad de Wolman/complicaciones , Enfermedad de Wolman/diagnóstico , Enfermedad de Wolman/enzimología , Enfermedad de Wolman/etnología , Enfermedad de WolmanAsunto(s)
Aborto Habitual/genética , Deleción Cromosómica , Cromosomas Humanos Y/genética , Femenino , Humanos , EmbarazoRESUMEN
Niemann-Pick type C disease (NPC) is a rare lysosomal disease with a protean presentation, ranging from a fatal neonatal course with visceromegaly to an adult presentation with only neurological or psychiatric symptomatology. In this report we describe the genetic and clinical characteristics of 3 Mexican patients from different families with juvenile presentation of NPC. Clinical examination, imaging of central nervous and gastrointestinal system, and EEG were performed. Genetic studies include sequencing and deletion/duplication analysis of NPC1 and NPC2 genes. All patients presented with cognitive impairment, ataxia, and supranuclear vertical gaze palsy; one case had gelastic cataplexy. Also they developed epilepsy and cortical atrophy and two patients had thinning of corpus callosum. The 3 patients were compound heterozygotes for NPC1 sequence variants, including 5 missense and 1 nonsense mutations: p.P1007A and p.F1087L in Case 1; p.Q921P and p.G992R in Case 2; and p.R348∗ and p.V1165M in case 3. Mexican patients with juvenile NPC presented with a variable clinical phenotype and compound heterozygosity. This suggests a relative high frequency of mutation carriers as it is reported for European population. Consequently, clinicians should consider NPC as a diagnosis possibility in any adolescent or young adult patient with juvenile dementia and/or ataxia, even in absence of gelastic cataplexy and supranuclear vertical gaze palsy.
RESUMEN
Abstract Background: Pediatric movement disorders represent a diagnostic challenge for pediatricians and pediatric neurologists due to their high clinical heterogeneity and shared common features. Therefore, specific diagnoses require different approaches including metabolic work-up and specific tests for frequent genetic conditions. Alternating hemiplegia of childhood (AHC) is an ultra-rare pediatric movement disorder, characterized by paroxysmal alternating hemiplegia, dystonia, and seizure-like episodes that can be misleading during the evaluation of a child with a movement disorder. Case report: We present a Mexican patient with abnormal movements referred to the Genetics clinic because of hyperammonemia and a possible organic acidemia. Our assessment did not find clinical features compatible with an inborn error of metabolism. A massively parallel sequencing approach with targeted panel sequencing was used to get a final diagnosis. A missense variant c.2839G>A (p.Gly947Arg) located at exon 21 of ATP1A3 gene was demonstrated. This variant (rs398122887) has been previously reported as de novo producing alternating hemiplegia of childhood (AHC). Conclusions: AHC is an ultra-rare syndrome presented as a movement disorder with seizure-like episodes and a unique facial phenotype. Clinicians should be aware of this combination in order to diagnose this condition in a timely manner. Massive parallel sequencing panels are emerging as the best approach to diagnose rare movement disorders and simultaneously rule out metabolic disorders and common epileptic syndromes.
Resumen Introducción: Los trastornos pediátricos del movimiento representan un reto diagnóstico para pediatras y neurólogos pediatras debido a su gran heterogeneidad clínica y características comunes compartidas. Por lo tanto, los diagnósticos específicos requieren de diferentes abordajes que incluyen la búsqueda de desórdenes metabólicos y pruebas específicas para condiciones genéticas frecuentes. La hemiplejia alternante de la infancia (AHC) es un trastorno pediátrico del movimiento poco común, caracterizado por cuadros paroxísticos de hemiplejia alternante, distonía y episodios semejantes a crisis epilépticas, que pueden resultar desorientadores durante el abordaje diagnóstico de un infante con un desorden del movimiento. Caso clínico: Presentamos una paciente mexicana con movimientos anormales referida a la Clínica de Genética por hiperamonemia y una posible acidemia orgánica. Nuestro abordaje no identificó características clínicas compatibles con un error innato del metabolismo. Se utilizó un abordaje basado en secuenciación masiva en paralelo para obtener un diagnóstico final. Se demostró una variante de sentido equivocado c.2839G>A (p.Gly947Arg) localizada en el exón 21 del gen ATP1A3. Esta variante (rs398122887) ha sido previamente reportada como de novo, ocasionando AHC. Conclusiones: La AHC es un síndrome excepcionalmente raro que se presenta con un trastorno del movimiento con cuadros semejantes a crisis epilépticas y un fenotipo facial particular. Los médicos deben ser conscientes de esta combinación con el fin de diagnosticar oportunamente esta condición. Los paneles de secuenciación masiva están emergiendo como el mejor abordaje para diagnosticar trastornos del movimiento raros y, simultáneamente, descartar trastornos metabólicos y síndromes epilépticos comunes.
Asunto(s)
Preescolar , Femenino , Humanos , ATPasa Intercambiadora de Sodio-Potasio/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Hemiplejía/diagnóstico , Hemiplejía/fisiopatología , Hemiplejía/genética , México , MutaciónRESUMEN
We report a Mexican girl showing the full blown clinical picture of mucopolysaccharidosis type II (MPSII). Iduronate-2-sulfatase (IDS) activity was low and she carried a heterozygous de novo c.1327C>T transition in exon 9, that changes codon 443 for a premature stop (TGA; p.Arg443(*)). Analysis of X-chromosome inactivation in androgen receptor (AR) locus showed a highly skewed ratio of 92:8 suggesting a functional hemizygosity with dominant expression of the mutant IDS and explaining the disease manifestation. This is one of the rare cases of females affected by MPSII due to the combined effect of a skewed X-chromosome inactivation and a de novo IDS mutation. We recommend that clinicians should consider the diagnosis of MPSII even in a girl without positive family history for this condition.