RESUMEN
OBJECTIVE: To report the type and frequency of chromosomal anomalies and Y-microdeletions among Hong Kong Chinese subfertile men with sperm concentrations lower than 5 million/mL. DESIGN. Retrospective study. SETTING: A reproductive centre in Hong Kong. PARTICIPANTS: A total of 295 Chinese subfertile men who underwent both karyotyping and Y-microdeletion studies from 2000 to 2007 were categorised as having non-obstructive azoospermia (n=71), very severe oligospermia (sperm concentration>0 and
Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Y , Infertilidad Masculina/epidemiología , Infertilidad Masculina/genética , Aberraciones Cromosómicas Sexuales/estadística & datos numéricos , Instituciones de Atención Ambulatoria , Bases de Datos Factuales , Hong Kong/epidemiología , Humanos , Cariotipificación , Masculino , Prevalencia , Estudios Retrospectivos , Recuento de EspermatozoidesRESUMEN
OBJECTIVES: To identify the extra chromosomal material on 46,XX,21p+ for prenatal diagnosis. DESIGN AND METHODS: Conventional cytogenetic studies using GTG (G bands by trypsin using Giemsa) and CBG (C bands by barium hydroxide using Giemsa) techniques were performed on chromosomes at metaphase obtained from cultured amniocytes and parental blood lymphocytes. Molecular cytogenetic techniques, QF-PCR (quantitative fluorescent polymerase chain reaction), FISH (fluorescent in-situ hybridization), and DA-DAPI (Distamycin A and 4,6-diamino-2-phenylindole) staining, were then used to clarify the extra material present on fetal chromosome 21 p. RESULTS: The extra material on fetal chromosome 21 p has originated from Yqh, most likely at PAR2 (the secondary pseudoautosomal region). The karyotype should be 46,XX,der(21)t(Y;21)(q12;p13)de novo.ish der(21)t(Y;21)(q12;p13) (EST Cdy16c07+). CONCLUSION: This case demonstrates the usefulness of molecular techniques in the investigation of rare chromosomal rearrangements.