Minor Agata, Wong Edgar Chan, Harmer Karynn, Ma Sai
Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, BC, Canada.
Prenat Diagn. 2007 Aug;27(8):743-7. doi: 10.1002/pd.1772.
The azoospermic factor (AZF) region is critical for normal spermatogenesis since microdeletions and partial deletions have been associated with infertility. We investigate the diagnostic ability of karyotyping in detecting clinically relevant Y chromosome deletions. The clinical significance of heterochromatin deletions, microdeletions and partial AZFc deletions is also evaluated.
A patient with a Yq deletion, affected by severe oligoasthenoteratozoospermia, underwent intracytoplasmic sperm injection (ICSI) which resulted in the birth of a healthy baby boy. The patient, his father and his son underwent Y chromosome microdeletion and partial AZFc deletion screening. We also studied the aneuploidy rate in the sperm of the patient by fluorescent in situ hybridization.
AZF microdeletions were absent in the family. However, microdeletion analysis confirmed that the Yq deletion was limited to the heterochromatin. We found a partial AZFc gr/gr deletion in all three family members. We observed an increased rate of sex chromosome aneuploidy in the infertile patient.
Cytogenetic analysis was misleading in identifying the Yq breakpoint. Infertility observed in the patient was associated with the gr/gr partial deletion. However, because of the incomplete penetrance of gr/gr deletions, the consequence of the vertical transmission of the deletion through ICSI remains unknown.
无精子症因子（AZF）区域对于正常精子发生至关重要，因为微缺失和部分缺失与不育症相关。我们研究了核型分析在检测临床相关Y染色体缺失方面的诊断能力。还评估了异染色质缺失、微缺失和部分AZFc缺失的临床意义。
一名患有Yq缺失、严重少弱畸精子症的患者接受了胞浆内单精子注射（ICSI），结果诞下一名健康男婴。对该患者及其父亲和儿子进行了Y染色体微缺失和部分AZFc缺失筛查。我们还通过荧光原位杂交研究了该患者精子中的非整倍体率。
该家族中不存在AZF微缺失。然而，微缺失分析证实Yq缺失仅限于异染色质。我们在所有三名家族成员中均发现了部分AZFc gr/gr缺失。我们观察到不育患者的性染色体非整倍体率增加。
细胞遗传学分析在确定Yq断点方面具有误导性。患者中观察到的不育症与gr/gr部分缺失有关。然而，由于gr/gr缺失的不完全外显率，通过ICSI进行缺失的垂直传递的后果仍然未知。
