Microdeleciones del gen AZF en varones azoospérmicos-oligozoospérmicos / AZF gene microdeletions in azoospermic–oligozoospermic males

Antecedentes y objetivo: La presencia de microdeleciones en las regiones del factor de azoospermia (AZF) del cromosoma Y (YCM) se considera la causa genética más frecuente de infertilidad masculina junto con el síndrome de Klinefelter. El objetivo del estudio fue investigar las frecuencias y tipo de YCM en hombres infértiles en Aragón y analizar la relación entre las hormonas sexuales, la concentración espermática y las microdeleciones en ellos.Pacientes y métodosEstudio descriptivo retrospectivo de 644 varones, durante el periodo 2006-2019, a los que se les realizo el cribado para YCM mediante YChromStrip (Operón, España) por PCR+hibridación reversa, espermiograma, cariotipo y medición de las hormonas sexuales.ResultadosLa frecuencia de YCM fue del 3,88% (25/644), no detectándose en ningún paciente con oligozoospermia leve ni normospérmico, es decir, en recuentos espermáticos superiores a 5×106/ml. El grupo de pacientes azoospérmicos fue el que presentó una frecuencia de YCM más elevada (14,58%, 14/96). Las deleciones en la región AZFc fueron las más frecuentes (68%). El 20% (5/25) de pacientes con YCM presentó además algún tipo de anomalía en el cariotipo que incluyeron aneuploidías, deleciones, duplicaciones o translocaciones. La concentración espermática fue significativamente menor y las concentraciones de FSH y LH significativamente mayores en el grupo de pacientes con YCM.ConclusionesEl cribado de YCM es una prueba clave en el abordaje diagnóstico de la infertilidad masculina. La obtención de un resultado genético adecuado permite elegir técnicas de reproducción asistida idóneas, prevenir tratamientos innecesarios y la transmisión de defectos genéticos a la descendencia. (AU)

Background and objective: The presence of microdeletions in the Y-chromosome azoospermia factor (AZF) region (YCMs) is considered the most frequent genetic cause of male infertility along with Klinefelter syndrome. The objective of this study was to investigate the frequencies and type of YCMs in infertile men in Aragon and to analyze the relationship between sex hormones, sperm count and microdeletions in them.Patients and methodsRetrospective descriptive study of 644 men who during 2006–2019 were screened for YCMs using YChromStrip (Operón, Spain) by PCR+reverse hybridization, spermiogram, karyotype and quantification of sex hormones.ResultsThe frequency of YCMs was 3.88% (25/644), not being detected in any patient with mild or normospermic oligozoospermia, that is, in sperm counts higher than 5×106/mL. The group of azoospermic patients was the one that presented a higher frequency of YCMs (14.58%, 14/96). Deletions in the AZFc region were the most frequent (68%). 20% (5/25) of patients with YCMs also presented some type of karyotype abnormality that included aneuploidies, deletions, duplications and/or translocations. Sperm count was significantly lower and FSH and LH concentrations significantly higher in the group of patients with YCMs.ConclusionsYCMs screening is a key test in the diagnostic approach to male infertility. Obtaining an adequate result allows choosing suitable assisted reproduction techniques, preventing unnecessary treatments and the transmission of genetic defects to offspring. (AU)

[AZF gene microdeletions in azoospermic-oligozoospermic males]. / Microdeleciones del gen AZF en varones azoospérmicos-oligozoospérmicos.

BACKGROUND AND OBJECTIVE: The presence of microdeletions in the Y-chromosome azoospermia factor (AZF) region (YCMs) is considered the most frequent genetic cause of male infertility along with Klinefelter syndrome. The objective of this study was to investigate the frequencies and type of YCMs in infertile men in Aragon and to analyze the relationship between sex hormones, sperm count and microdeletions in them. PATIENTS AND METHODS: Retrospective descriptive study of 644 men who during 2006-2019 were screened for YCMs using YChromStrip (Operón, Spain) by PCR+reverse hybridization, spermiogram, karyotype and quantification of sex hormones. RESULTS: The frequency of YCMs was 3.88% (25/644), not being detected in any patient with mild or normospermic oligozoospermia, that is, in sperm counts higher than 5×106/mL. The group of azoospermic patients was the one that presented a higher frequency of YCMs (14.58%, 14/96). Deletions in the AZFc region were the most frequent (68%). 20% (5/25) of patients with YCMs also presented some type of karyotype abnormality that included aneuploidies, deletions, duplications and/or translocations. Sperm count was significantly lower and FSH and LH concentrations significantly higher in the group of patients with YCMs. CONCLUSIONS: YCMs screening is a key test in the diagnostic approach to male infertility. Obtaining an adequate result allows choosing suitable assisted reproduction techniques, preventing unnecessary treatments and the transmission of genetic defects to offspring.