Infertility in humans is surprisingly common occurring in approximately 15% of the population wishing to start a family. Despite this, the molecular and genetic factors underlying the cause of infertility remain large...Infertility in humans is surprisingly common occurring in approximately 15% of the population wishing to start a family. Despite this, the molecular and genetic factors underlying the cause of infertility remain largely undiscovered. Nevertheless, more and more genetic factors associated with infertility are being identified. This review will focus on our current understanding of the chromosomal basis of male infertility specifically： chromosomal aneuploidy, structural and numerical karyotype abnormalities and Y chromosomal microdeletions. Chromosomal aneuploidy is the leading cause of pregnancy loss and developmental disabilities in humans. Aneuploidy is predominantly maternal in origin, but concerns have been raised regarding the safety of intracytoplasmic sperm injection as infertile men have significantly higher levels of sperm aneuploidy compared to their fertile counterparts. Males with numerical or structural karyotype abnormalities are also at an increased risk of producing aneuploid sperm. Our current understanding of how sperm aneuploidy translates to embryo aneuploidy will be reviewed, as well as the application of preimplantation genetic diagnosis （PGD） in such cases. Clinical recommendations where possible will be made, as well as discussion of the use of emerging array technology in PGD and its potential applications in male infertility.展开更多
Dear Editor,Chromosome heteromorphisms are described as variations in size and morphology at specific regions that can be detected through classical banding methods.They are mitotically stable variants usually present...Dear Editor,Chromosome heteromorphisms are described as variations in size and morphology at specific regions that can be detected through classical banding methods.They are mitotically stable variants usually present in a heterozygous state(only one of the homologous chromosomes is heteromorphic).In humans,the most commonly detected heteromorphisms involve the heterochromatic regions of chromosomes 1,9,16,and Y(designated as lqh,9qh,16qh,and Yqh,respectively),and the short-arms,satellites,or stalks of the acrocentric chromosomes 13,14,15,21,and 22(e.g,for chromosome 13 designated as 13p.13ps,and 13pstk,respectively).Pericentric inversions involving the heterochromatic region of chromosomes l,9,and Y are also frequently observed.展开更多
Objective: The inicidence of miscarriage is correlated with maternal age. The majority of miscarriages are chromosomally abnormal. The purpose of this study was to determine in a large population of infertility patien...Objective: The inicidence of miscarriage is correlated with maternal age. The majority of miscarriages are chromosomally abnormal. The purpose of this study was to determine in a large population of infertility patients (>2000 cycles) if preimplantation genetic diagnosis (PGD) reduced the rate of spontaneous abortions. Design: Multicenter retrospective controlled study. Setting: One hundred IVF centers referring samples to a reference PGD laboratory. Patient(s): Infertile women. Intervention(s): The spontaneous abortion rate after PGD was retrospectively compared to non- PGD cycles from the 2002 American Society for Reproductive Medicine- Society for Assisted Reproduction Technology report on IVF cycles. Main Outcome Measure(s): Spontaneous abortions and trisomic offspring rates. Result(s): The study included 2,279 cycles of PGD. The pregnancy rate per retrieval was 26.7% (average age 39.6). The mean pregnancy loss for the PGD group (0.167) was significantly lower than for the general IVF group (0.215) (P < .001). After PGD, the spontaneous abortion rate was 14.1% for ages 35- 40, and 22.2% for women over 40, compared to 19.4% (P=.03) and 40.6% (P < .001), respectively, in controls. The clinical error rate of PGD (1.2% ) was significantly lower than expected (4.7% ) (P < .001). Conclusion(s): The data suggests that PGD significantly reduces the risk of spontaneous abortions in women undergoing IVF and PGD, particularly in women over 40. In addition, PGD may also reduce the risk of trisomic offspring.展开更多
文摘Infertility in humans is surprisingly common occurring in approximately 15% of the population wishing to start a family. Despite this, the molecular and genetic factors underlying the cause of infertility remain largely undiscovered. Nevertheless, more and more genetic factors associated with infertility are being identified. This review will focus on our current understanding of the chromosomal basis of male infertility specifically： chromosomal aneuploidy, structural and numerical karyotype abnormalities and Y chromosomal microdeletions. Chromosomal aneuploidy is the leading cause of pregnancy loss and developmental disabilities in humans. Aneuploidy is predominantly maternal in origin, but concerns have been raised regarding the safety of intracytoplasmic sperm injection as infertile men have significantly higher levels of sperm aneuploidy compared to their fertile counterparts. Males with numerical or structural karyotype abnormalities are also at an increased risk of producing aneuploid sperm. Our current understanding of how sperm aneuploidy translates to embryo aneuploidy will be reviewed, as well as the application of preimplantation genetic diagnosis （PGD） in such cases. Clinical recommendations where possible will be made, as well as discussion of the use of emerging array technology in PGD and its potential applications in male infertility.
基金(Agency for Management of University and Research Grants,Spain)and UAB C F-180034 grant(Autonomous University of Barcelona).
文摘Dear Editor,Chromosome heteromorphisms are described as variations in size and morphology at specific regions that can be detected through classical banding methods.They are mitotically stable variants usually present in a heterozygous state(only one of the homologous chromosomes is heteromorphic).In humans,the most commonly detected heteromorphisms involve the heterochromatic regions of chromosomes 1,9,16,and Y(designated as lqh,9qh,16qh,and Yqh,respectively),and the short-arms,satellites,or stalks of the acrocentric chromosomes 13,14,15,21,and 22(e.g,for chromosome 13 designated as 13p.13ps,and 13pstk,respectively).Pericentric inversions involving the heterochromatic region of chromosomes l,9,and Y are also frequently observed.
文摘Objective: The inicidence of miscarriage is correlated with maternal age. The majority of miscarriages are chromosomally abnormal. The purpose of this study was to determine in a large population of infertility patients (>2000 cycles) if preimplantation genetic diagnosis (PGD) reduced the rate of spontaneous abortions. Design: Multicenter retrospective controlled study. Setting: One hundred IVF centers referring samples to a reference PGD laboratory. Patient(s): Infertile women. Intervention(s): The spontaneous abortion rate after PGD was retrospectively compared to non- PGD cycles from the 2002 American Society for Reproductive Medicine- Society for Assisted Reproduction Technology report on IVF cycles. Main Outcome Measure(s): Spontaneous abortions and trisomic offspring rates. Result(s): The study included 2,279 cycles of PGD. The pregnancy rate per retrieval was 26.7% (average age 39.6). The mean pregnancy loss for the PGD group (0.167) was significantly lower than for the general IVF group (0.215) (P < .001). After PGD, the spontaneous abortion rate was 14.1% for ages 35- 40, and 22.2% for women over 40, compared to 19.4% (P=.03) and 40.6% (P < .001), respectively, in controls. The clinical error rate of PGD (1.2% ) was significantly lower than expected (4.7% ) (P < .001). Conclusion(s): The data suggests that PGD significantly reduces the risk of spontaneous abortions in women undergoing IVF and PGD, particularly in women over 40. In addition, PGD may also reduce the risk of trisomic offspring.
