Association of the EPAS1 rs7557402 Polymorphism with Hemodynamically Significant Patent Ductus Arteriosus Closure Failure in Premature Newborns under Pharmacological Treatment with Ibuprofen.

Patent ductus arteriosus (PDA) is frequent in preterm newborns, and its incidence is inversely associated with the degree of prematurity. The first choice of pharmacological treatment is ibuprofen. Several genes, including EPAS1, have been proposed as probable markers associated with a genetic predisposition for the development of PDA in preterm infants. EPAS 1 NG_016000.1:g.84131C>G or rs7557402 has been reported to be probably benign and associated with familial erythrocytosis by the Illumina Clinical Services Laboratory. Other variants of EPAS1 have been previously reported to be benign for familial erythrocytosis because they decrease gene function and are positive for familial erythrocytosis because the overexpression of EPAS1 is a key factor in uncontrolled erythrocyte proliferation. However, this could be inconvenient for ductal closure, since for this process to occur, cell proliferation, migration, and differentiation should take place, and a decrease in EPAS1 gene activity would negatively affect these processes. Single-nucleotide polymorphisms (SNPs) in EPAS1 and TFAP2B genes were searched with high-resolution melting and Sanger sequencing in blood samples of preterm infants with hemodynamically significant PDA treated with ibuprofen at the National Institute of Perinatology. The variant rs7557402, present in the EPAS1 gene eighth intron, was associated with a decreased response to treatment (p = 0.007, OR = 3.53). The SNP rs7557402 was associated with an increased risk of pharmacological treatment failure. A probable mechanism involved could be the decreased activity of the product of the EPAS1 gene.

Frequent copy number variants in a cohort of Mexican-Mestizo individuals.

BACKGROUND: The human genome presents variation at distinct levels, copy number variants (CNVs) are DNA segments of variable lengths that range from several base pairs to megabases and are present at a variable number of copies in human genomes. Common CNVs have no apparent influence on the phenotype; however, some rare CNVs have been associated with phenotypic traits, depending on their size and gene content. CNVs are detected by microarrays of different densities and are generally visualized, and their frequencies analysed using the HapMap as default reference population. Nevertheless, this default reference is inadequate when the samples analysed are from people from Mexico, since population with a Hispanic genetic background are minimally represented. In this work, we describe the variation in the frequencies of four common CNVs in Mexican-Mestizo individuals. RESULTS: In a cohort of 147 unrelated Mexican-Mestizo individuals, we found that the common CNVs 2p11.2 (99.6%), 8p11.22 (54.5%), 14q32.33 (100%), and 15q11.2 (71.1%) appeared with unexpectedly high frequencies when contrasted with the HapMap reference (ChAS). Yet, while when comparing to an ethnically related reference population, these differences were significantly reduced or even disappeared. CONCLUSION: The findings in this work contribute to (1) a better description of the CNVs characteristics of the Mexican Mestizo population and enhance the knowledge of genome variation in different ethnic groups. (2) emphasize the importance of contrasting CNVs identified in studied individuals against a reference group that-as best as possible-share the same ethnicity while keeping this relevant information in mind when conducting CNV studies at the population or clinical level.

Unravelling complex mosaicism of sex chromosomes in a patient with primary amenorrhea through cytogenetic analysis on urothelial cells.

OBJECTIVE: Sex chromosome mosaicism remains challenging in the study of disorders of sex development (DSD). Aneuploid cells in the developing gonad play a major role in sex determination. Therefore, it is necessary acknowledge their presence by different methods. Our aim was to stand out the utility of urothelial cells for unravelling complex and hidden cell lines in DSD patients. CASE REPORT: Herein we report on a 19-year-old female with primary amenorrhea, short stature without ambiguous external genitalia. She had a 45,X/46, XY karyotype in leukocytes. Interphase FISH revealed hidden 45,X/47,XYY/47,XXY/46,XY/46, XX mosaicism in leukocytes and urothelial cells. CONCLUSION: These findings highlight the importance of investigating sex chromosome mosaicism in other tissues. Of particular interest in cases of DSD are the cells from the urinary epithelium, which may reflect the cell composition of the urogenital ridge, the analysis of these cells should be considered within the clinical assessment of DSD patients.

Considerations on genetic engineering: regarding the birth of twins subjected to gene edition.

In this essay, the bioethical implications of the recent genetic manipulation in human embryos with CRISPR-Cas9 to eliminate the CCR5 gene and the birth of a pair of discordant twin girls are analyzed. The experiment was disseminated via social media. The main bioethical flaws identified include the justification of the model, the informed consent process and the lack of disclosure of evident conflicts of interest. The consequences of the experiment on the life of the twins that were born were not properly evaluated, such as the impact on their autonomy, the alleged benefits to be received and the future risks of harm during their lifetime. Having manipulated the germ cell line, the effects on their future offspring were not considered. This type of actions negatively affects the way society conceives science. Genetic engineering should be reserved to the basic experimental context or as clinical research for the correction of known serious diseases of genetic origin under strict regulatory and bioethical supervision and using a gradualist approach in accordance with the advances of gene editing techniques.

En este ensayo se analizan las implicaciones bioéticas de la reciente manipulación genética en embriones humanos con CRISPR-Cas9 para eliminar el gen CCR5 y el nacimiento de dos gemelas discordantes. El experimento se divulgó en medios sociales. Los principales problemas bioéticos identificados son la justificación del modelo, el proceso de consentimiento informado y la falta de declaración de evidentes conflictos de interés. No se evaluaron apropiadamente las consecuencias del experimento sobre la vida de las gemelas nacidas como la afectación a su autonomía, los supuestos beneficios por recibir y los riesgos futuros de daño durante su vida. Habiendo manipulado la línea celular germinal, no se consideraron los efectos sobre su descendencia futura. Este tipo de acciones tiene un impacto negativo en la forma como la sociedad concibe la ciencia. La ingeniería genética debe reservarse al contexto experimental básico o bien como investigación cínica para la corrección de enfermedades conocidas graves de origen genético, bajo estricta supervisión regulatoria y bioética y de manera gradualista de acuerdo con el progreso de las técnicas de edición genética.

Reflexiones sobre la ingeniería genética: a propósito del nacimiento de gemelas sometidas a edición génica / Considerations on genetic engineering: regarding the birth of twins subjected to gene edition

Resumen En este ensayo se analizan las implicaciones bioéticas de la reciente manipulación genética en embriones humanos con CRISPR-Cas9 para eliminar el gen CCR5 y el nacimiento de dos gemelas discordantes. El experimento se divulgó en medios sociales. Los principales problemas bioéticos identificados son la justificación del modelo, el proceso de consentimiento informado y la falta de declaración de evidentes conflictos de interés. No se evaluaron apropiadamente las consecuencias del experimento sobre la vida de las gemelas nacidas como la afectación a su autonomía, los supuestos beneficios por recibir y los riesgos futuros de daño durante su vida. Habiendo manipulado la línea celular germinal, no se consideraron los efectos sobre su descendencia futura. Este tipo de acciones tiene un impacto negativo en la forma como la sociedad concibe la ciencia. La ingeniería genética debe reservarse al contexto experimental básico o bien como investigación cínica para la corrección de enfermedades conocidas graves de origen genético, bajo estricta supervisión regulatoria y bioética y de manera gradualista de acuerdo con el progreso de las técnicas de edición genética.

Abstract In this essay, the bioethical implications of the recent genetic manipulation in human embryos with CRISPR-Cas9 to eliminate the CCR5 gene and the birth of a pair of discordant twin girls are analyzed. The experiment was disseminated via social media. The main bioethical flaws identified include the justification of the model, the informed consent process and the lack of disclosure of evident conflicts of interest. The consequences of the experiment on the life of the twins that were born were not properly evaluated, such as the impact on their autonomy, the alleged benefits to be received and the future risks of harm during their lifetime. Having manipulated the germ cell line, the effects on their future offspring were not considered. This type of actions negatively affects the way society conceives science. Genetic engineering should be reserved to the basic experimental context or as clinical research for the correction of known serious diseases of genetic origin under strict regulatory and bioethical supervision and using a gradualist approach in accordance with the advances of gene editing techniques.

An increase in IL-1ß concentrations in embryo culture-conditioned media obtained by in vitro fertilization on day 3 is related to successful implantation.

PURPOSE: This study aimed to evaluate interleukin (IL)-1ß concentrations in maternal serum and in embryo-cultured conditioned media and to correlate these findings with success of implantation. METHODS: A total of 70 infertile women who underwent in vitro fertilization treatment were studied. IL-1ß concentrations were quantified in maternal serum and in embryo culture-conditioned media on days 1 and 3. The findings were compared between those who achieved pregnancy and those who did not. RESULTS: No significant differences were found in IL-1ß serum concentrations between the groups. IL-1ß was not detected in day 1 culture-conditioned medium. On day 3, IL-1ß was quantified in 27 patients, and IL-1ß concentrations were significantly higher in women who achieved pregnancy than in those who did not (p < 0.001). CONCLUSIONS: High IL-1ß concentrations in day 3 culture-conditioned medium in patients who achieve pregnancy after in vitro fertilization treatment indicate a possible role of embryonic IL-1ß in the implantation process.

[Current indications for invasive prenatal diagnosis. New proposals based on the experience of Institute Nacional de Perinatología]. / Indicaciones actuales para el diagnóstico prenatal invasivo. Nuevas propuestas basadas en la experiencia del Instituto Nacional de Perinatología.

BACKGROUND: Invasive prenatal diagnosis (IPD) allows identification of fetal diseases, mainly aneuploidy. With the addition of first-trimester prenatal screening and structural ultrasound, IPD indications have changed. OBJECTIVE: To describe the current indications for IPD in pregnant patients at INPer. METHODS: Descriptive and retrospective study. We reviewed medical records of patients in which IPD was performed during a period of 2.5 years. RESULTS: A total of 339 studies were performed: 81% by amniocentesis (AC), 13% by chorionic villus sampling (CVS) and 6% by cordocentesis or somatocentesis. The most common indications for AC were: advanced maternal age (AMA) (43%), fetuses with multiple defects by ultrasonido (23%) and presence of soft markers for aneuploidies (9%). For CVS were: cystic hygroma (24%). Increased nuchal translucency (NT) (24%), and AMA (18%). When the indication was only AMA, 1.5% of fetus presented aneuploidy. In women under 38 years and normal ultrasoud, chromosomal abnormalities were not detected. The increased NT in women <35 years had a 21% detection and in patients > 35 years it increased to 33%. CONCLUSIONS: We observed that the group who had normal translucencia nucal and AMA presented a low risk of chromosomal abnormalities. In the presence of an increased NT, 33% of fetuses were affected, so that measuring TN is considered the best non invasive PD tool. The average age with cytogenetic abnormalities was above 38 years, so we suggest to offer IPD in women above 38 years-old.

MLPA (amplificación de sondas dependiente de ligandos múltiples) en el diagnóstico perinatal rápido de las principales aneuploidías / MLPA (multiplex ligation-dependent probe amplification) in perinatal rapid diagnosis of major aneuploidies

Introducción: El MLPA (amplificación de sondas dependiente de ligandos múltiples) es un método reciente, basado en la reacción en cadena de la polimerasa (RCP), de cuantificación relativa del número de copias normales y anormales de ácido desoxirribonucleico (ADN) de hasta 40 secuencias genómicas diferentes. Su uso se ha difundido tanto en la investigación como en el diagnóstico clínico. Recientemente, el MLPA se ha utilizado en diagnóstico prenatal y en el estudio de abortos. Objetivo: Presentar los primeros resultados obtenidos con MLPA en el diagnóstico perinatal de las principales aneuploidías de los cromosomas 13, 18, 21, X y Y. Material y métodos: Se obtuvo ácido desoxirribonucleico genómico de tejidos sin cultivar de aborto, biopsia de vellosidades coriales (VC), líquido amniótico (LA), cordón umbilical (CU) de óbitos o sangre periférica (SP) de recién nacidos, en 13 casos con patología perinatal. Para el MLPA se utilizó el kit p 290 para diagnóstico prenatal y sus productos se cuantificaron en un secuenciador ABI Prism 3130. Todos los casos se procesaron para cariotipo en forma paralela. Resultados: Se obtuvieron resultados con MLPA entre dos y tres días en las 13 muestras estudiadas. Seis de ellas mostraron aneuploidías. El cariotipo se obtuvo entre 15 y 21 días en 11 casos, cinco fueron aneuploides y dos fallaron. Los resultados entre MLPA y cariotipo fueron concordantes en las fallas del cultivo celular, el diagnóstico se obtuvo por MLPA. Conclusiones: El MLPA es un método útil y rápido en el diagnóstico perinatal de las principales aneuploidías; además, tiene la ventaja de permitir estudiar tejidos con baja viabilidad celular como ocurre en algunos casos de aborto u óbito.

Introduction: The MLPA (multiplex ligation-dependent probe amplification) is a new method based on polimerase chain reaction (PCR) for relative quantification of normal and abnormal numbers of copies of desoxyribonucleic (DNA), up to 40 different genomic sequences. Its use is widespread in both, research and clinical diagnosis. MLPA recently began to be used in prenatal diagnosis and study of pregnancy losses. Objective: Present the first results obtained with MLPA in perinatal diagnosis of major aneuploidies of chromosomes 13, 18, 21, X and Y. Methods: Genomic DNA was obtained from different uncultivated tissues: abortion, chorionic villus, amniotic fluid, umbilical cord blood or peripheral blood in 13 cases with perinatal pathology. MLPA kit p290 for prenatal diagnosis was used and its products were quantified in ABI Prism 3130 sequencer. All cases were processed in parallel for karyotype. Results: MLPA results were obtained in 2 to 3 days in the 13 samples studied. Six of them showed aneuploidy. Karyotype was obtained between 15 and 21 days in 11 cases, five were aneuploidy and two failed. The results obtained with MLPA and karyotypes were concordant and in cases where the cell culture failed, the diagnosis was obtained by MLPA. Conclusions: MLPA is a rapid and useful method in the perinatal diagnosis of major aneuploidies, it also has the advantage of allowing the study of tissues with low cell viability, as in some cases of abortion and fetal death.

El papel de la genética en la restricción del crecimiento intrauterino / The role of genetics in fetal growth restriction

Se define como restricción del crecimiento intrauterino (RCIU) a la alteración en el crecimiento fetal que determina un peso por debajo de la percentila 10 para la edad gestacional. Las causas genéticas de RCIU pueden dividirse en: cromosómicas, alteraciones de la epigenética o impronta y síndromes génicos. Se presenta el caso de una paciente con RCIU referida por sospecha de displasia ósea, en la que se descartó disfunción vascular placentaria por ultrasonido prenatal, infecciones, patología materna y displasias óseas por estudio radiológico normal. Se realizó cariotipo en el cordón umbilical y en tres diferentes sitios de la placenta por la posibilidad de un mosaico placentario, obteniéndose un resultado normal. Al nacimiento presentó peso y talla por debajo de la percentila 3, cráneo dolicocéfalo con frontal prominente, fontanela anterior amplia, cara pequeña, triangular con mentón en punta y clinodactilia bilateral. A los dos meses de edad se observó asimetría de extremidades inferiores y se refirió reflujo gastroesofágico. Con base en los criterios clínicos y resultados obtenidos se realizó el diagnóstico de síndrome de Silver-Russell.

Intrauterine growth restriction (IUGR) is an alteration in fetal development in which the fetal weight is below the 10th percentile for gestational age. The genetic causes of IUGR can be classified as: chromosomal, epigenetic and other imprinting disorders and monogenic syndromes. We report a patient with IUGR referred to our hospital with the prenatal diagnosis of achondroplasia. Vascular malfunction of the placentae, maternal pathology, and skeletal dysplasia were discarded. A karyotype in umbilical cord and in three different placental spots was performed, with a normal result in all of them, ruling out placentae mosaicism. At birth, the weight and height were below the 3th percentile. Physical examination showed: dolicocephaly, frontal prominence, large fontanels, small and triangular face, pointed chin and incurved bilateral fifth fingers. Two months later a lower limb asymmetry was noticed and gastroesophageal reflux was referred. With these clinical abnormalities and the studies performed the diagnosis of Silver-Russell syndrome was established.

[Genetic disease and diagnostic strategies in stillbirth]. / Alteraciones genéticas y estrategias diagnósticas en muerte fetal.

BACKGROUND: Stillbirth occurs in about 1 in 1000 pregnancies. The causes are maternal, fetal, and placental; but in half of the cases, no cause can be determined. Genetic disease, a common cause of stillbirth, is diagnosed in 25-35% of patients with birth defects. OBJECTIVE: Describe birth defects found in stillbirth cases at the Instituto Nacional de Perinatología in a period of 3 years, analyze risk factors in each pregnancy, and propose an adequate approach to effectively reach the proper diagnosis of defined genetic entities related to stillbirth. MATERIAL AND METHODS: All stillbirths cases presenting birth defects and assessed by the Department of Genetics from January 2008 to December 2010 were included in this study. RESULTS: We evaluated 55 stillbirths with birth defects. 31% of them showed multiple defects; 14.5%, single defects; 20%, single gene disorders; 14.5%, chromosomal abnormalities; 9%, disruptive processes; 7%, non-immune fetal hydrops, and 4% twin pregnancy. The karyotype was obtained in all cases from amniocentesis, and in half of them from umbilical cords as well. In 95% of the cases prenatal findings were confirmed through prenatal USG, and necropsy was performed in 74.5% of them. CONCLUSION: Ultrasound, karyotype, autopsy and assessment by a medical geneticist allowed an accurate diagnosis in 81% of cases. Genetic counseling helps reduce parental anxiety and stillbirth from unknown causes.

[Prenatal diagnosis by amniocentesis. Clinical and cytogenetic experience in 1,500 cases]. / Diagnóstico prenatal por amniocentesis. Experiencia clínica y citogenética en 1,500 casos.

BACKGROUND: Genetic amniocentesis is performed in México 25 years ago but only few works have been published. OBJECTIVE: To analyze clinical and cytogenetic findings in consecutive patients submitted to genetic amniocentesis. MATERIAL AND METHOD: An analysis was made of the clinical features, amniocentesis results and pregnancy outcome in 1500 consecutive cases of genetic amniocentesis. RESULTS: Sixty-eight fetuses with chromosomopathy (4.5%) were detected and two, with an inborn error of metabolism. The most frequent abnormalities were trisomy 21 (32 cases), trisomy 18 (10 cases), trisomy 13(6 cases), 45,X (6 cases), 47,XXY (4 cases). Pregnancy outcome is known in 474 patients (32%). There were five fetal losses (1%). Of the 68 cases with chromosomopathy, the outcome is known in 45, of which, 29 (64%) decided to have an abortion while 16 (35%) continued the pregnancy, six had a spontaneous abortion or perinatal death and ten had an alive new born. Among fetuses with normal or balanced karyotype and normal ultrasound, 11 out of 419 (2.6%) had congenital anomalies. Two of them had a condition known to be related with epigenetic regulation, (Russell Silver and Angelman syndrome). CONCLUSIONS: Amniocentesis is a reliable and low risk method. Cytogenetic findings in this series are similar to those reported in the literature. Most patients with fetal disease decided to have an abortion. The finding of two patients with a condition related with abnormal epigenetic regulation suggests that the magnitude of this risk remains to be defined.

[Birth defects associated with increased nuchal translucency]. / Defectos congénitos asociados con translucencia nucal aumentada.

BACKGROUND: Nuchal translucency is widely used to screen for trisomy 21 in the first trimester of pregnancy. It has also been associated with other chromosomal abnormalities, genetic syndromes and congenital defects. OBJECTIVE: To evaluate the perinatal outcome of patients who showed nuchal translucency greater or equal to 95th percentile during the first trimester ultrasound screening, which underwent fetal karyotype. MATERIAL AND METHOD: Case series. Fetuses with nuchal translucency greater or equal to 95th percentile were evaluated by fetal karyotype, second-trimester structural ultrasound scan, fetal echocardiography and postnatal clinical genetic evaluation, attended in the servicio de Genética of the Instituto Nacional de Perinatología Isidro Espinosa de los Reyes. RESULTS: 48 fetuses were evaluated. The karyotype was normal in 39 (81%) and abnormal in 9 (19%) cases of which three had trisomy 21, three monosomy X, two trisomy 18 and one 47,XYY In the cases with normal karyotype, 13 (33%) showed an abnormal second trimester ultrasound scan; among them, 12 had major congenital defects, 5 of them had abnormal cardiac findings that were confirmed by fetal echocardiography. In the group of 26 fetuses with normal karyotype and ultrasound, only 2 patients had minor birth defects. CONCLUSIONS: Increased fetal nuchal translucency is frequently associated with chromosomal abnormalities and several congenital defects, mostly heart defects and genetic syndromes. Our findings are in accordance with other published reports where a complete follow-up of all patients with increased nuchal translucency is recommended even if they have a normal karyotype, due to the increased risk of having other congenital defects or syndromic entities.

Actitud y aceptación de las mujeres embarazadas hacia el diagnóstico citogenético prenatal / Attitude to an acceptance of prenatal cytogenetic diagnosis by pregnant women

Los métodos de diagnóstico citogenético prenatal implican la toma de decisión relativa al riesgo de los procedimientos y plantearse la posibilidad de un resultado anormal. Se aplicó un cuestionario a 264 mujeres embarazadas con el fin de conocer las características de las mujeres que se los realizan y los factores relacionados con la aceptación de los procedimientos. Aceptaron realizarse los estudios 209 mujeres (79 por ciento). La aceptación tuvo relación directa con el grado escolaridad e inversa con el grado de religiosidad. El entrevistador que aplicó el custionario no influyó en la decisión, pero sí contó con información previa. Las mujeres de mayor nivel socioeconómico, mayor escolaridad y que practican poco su religión aceptan la posibilidad de interrumpir el embarazo

Secuencia de oligohidramnios y presentación pélvica

Se presenta el caso clínico de un recién nacido con múltiples deformaciones craneofaciales y esqueléticas, en quien se estableció el diagnóstico de secuencia de oligohidramnios y de presentación pélvica. Se discute la etiología y fisiopatogenia, así como el pronóstico y asesoramiento genético en estos casos