ABSTRACT
Resumen ANTECEDENTES El análisis citogenético del síndrome de Turner suele ser una línea monosómica X. Son raros los casos reportados con más de una línea celular y aún menos con aberraciones estructurales del cromosoma Y. No es común que se incluyan análisis dermatoglíficos. CASO CLÍNICO Paciente de 8 años de edad, que al examen físico no evidenció ninguna característica fenotípica propia del síndrome de Turner, excepto talla baja, 1.28 cm (por debajo del percentil 3). La laparoscopia exploradora mostró al útero hipoplásico, trompas rudimentarias, cintillas ováricas hipoplásicas delgadas y anillos inguinales normales sin evidencia de hernias, no se detectó tejido testicular. El resultado de la citogenética convencional en sangre periférica fue de: 46,XY; bandeo "C" 46,XY; FISH 45,X[230]/46,XY[117]/46,X,dic.Y[64]. La dactiloscopia con aumento de verticilos coincidió con el aumento del número de crestas mayor al reportado como normal (127 ± 0.8), en quiroscopia ángulo ATD (92°), número de crestas a-b (86) y el porcentaje de t (24.3%). CONCLUSIÓN Se discute uno de los pocos casos reportados en la bibliografía de síndrome de Turner con tres líneas celulares diferentes, resultantes de un evento no disfuncional poscigótico y estructural cromosómico, así como el análisis de la dactiloscopia y quiroscopia y los aspectos genéticos, medio ambientales y bioquímicos de los dermatoglifos, coincidentes con los del síndrome clásico.
Abstract BACKGROUND Usually, cytogenetic analysis of Turner´s syndrome is presented as a single monosomic X cell line. Are rare the reported cases in which there are multiple cell lines and even less frequent descriptions of structural chromosomal aberrations of the Y-chromosome. Additionally, the cases reported to date do not include finger/palm process analysis. We present an infrequent case of a Turner syndrome with three different cell lines including a structural aberration of the Y-chromosome and to correlate with finger process and palm process analysis. CLINICAL CASE A 8-year-old female patient who did not show any Turnerian syndrome phenotypic characteristics except low height, 1.28 cm (under 3th percentile). Exploratory laparoscopy shows hypoplastic uterus, with rudimentary tubes, thin hypoplastic ovaries and normal inguinal rings without evidence of hernias. No testicular tissue was detected. Conventional cytogenetic findings in peripheral blood are: 46, XY; "C" banding 46, XY; FISH 45, X [230] / 46, XY [117] /46,X,dic.Y [64]. Finger process with increase of whorls was observed, coinciding with the increase in the number of ridges higher than that reported as normal (127 ± 0.8) and in the palm process the atd angle (92º), number of a-b crests (86) and the percentage of t (24.3%). CONCLUSION We discuss one of the few cases reported in the scientific literature of Turner syndrome with three different cell lines results from a non-dysfunctional post-zygotic etiology and its chromosomic structure; as well as the results of genetic, environmental and biochemical aspects of the finger/palm process and their correlation with the classical syndrome.
ABSTRACT
OBJECTIVE: The accurate evaluation of a marker chromosome has been limited during prenatal karyotyping. We proposed a method of step-by-step approach to evaluate the origin of a marker chromosome. METHODS: A patient with 19 weeks of gestation was transferred to our hospital for karyotyping due to abnormal Triple test. Karyotyping of amniotic fluid was performed. NOR (nucleolar organizer region) banding and FISH (fluorescence in situ hybridization) using two types of sex chromosome probes: chromosome X alpha satellite probe (DXZI) & chromosome Y alpha satellite probe (DYZ3)(Cytocell, Bambury, UK) and CEP X/Y (Xp11.1-q11.1 CEP X alpha satellite & Yq12 CEP Y satellite III)(Vysis, IL, USA) were done. RESULTS: The routine chromosomal analysis showed 46,X,+mar. As the result of NOR banding, we supposed that the marker chromosome was less likely originated from acrocentric chromosomes. FISH analysis revealed Y centromere signal on marker chromosome, but Yq12 signal was not detected. Therefore the marker chromosome was identified as Y chromosome formed by deletion at Yq11.2. CONCLUSION: This study demonstrated that FISH and NOR banding technique is more effective method for a marker chromosome evaluation during prenatal karyotyping.