Effect of paternal age on human sperm chromosomes
E M Sartorelli1, L F Mazzucatto, J M de Pina-Neto
1Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciĕncias Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil. elza@ccb.ufsc.br
Objective:
To investigate whether increased age alters the frequency and type of chromosomal anomalies in human spermatozoa.
Design:
Semen specimens were collected from donors via masturbation; cytogenetic studies were performed on sperm chromosomes after heterologous (human-hamster) in vitro fertilization.
Setting:
Cytogenetics Laboratory, Genetics Department, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil.
Patient(S):
Seven men ages 59-74 (older group) and five men ages 23-39 (control group).
Main Outcome Measure(S):
Frequency and types of chromosomal anomalies in older and control group donors.
Result(S):
The frequency of numerical and structural aberrations (acentric fragments and complex radial figures) was significantly greater in chromosomes of older donors when compared with those of the control group.
Conclusion(S):
The higher frequency of sperm chromosome aberrations in older men was mainly a result of increased nondisjunction, acentric fragments, and complex radial figures.
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