Effect of sY1192 single-locus microdeletion in the AZFb/c region on spermatogenesis and pregnancy outcomes
Authors: Chen Gangxin , Sun Yan , Chen Yongyan , Yang Rui , Li Haiyan , Zheng Beihong 
Published: September 2023

Backgroud: Y chromosome microdeletions is an important cause of male infertility. At present, research on the Y chromosome mainly focuses on analyzing the loss of large segments of the AZFabc gene, and few people have studied the impact of unit point deletion in the AZF band on fertility.
Methods: A total of 15 associated sequence tag site loci in the AZF region of the Y chromosome in 2,000 patients with oligoasthenospermia were tested, and 116 patients with AZF microdeletion were selected. Calculated the proportion of azoospermia caused by the sY1192 deletion. The proportion and type of sY1192 independent and combined deletions in the AZFb/c region were determined to analyze the changes in the associated sex hormone levels due to the loss of sY1192 and the pregnancy outcomes of patients with weak or obstructive assisted reproductive techniques to assist in pregnancy.
Results: Among the 116 patients with AZF microdeletion, the sY1192-independent deletion accounted for 41.38% (48/116), and the sY1192 combined deletion with other loci accounted for 25.86% (30/116). Eight patterns were found in the deletions associated with sY1192: the independent deletion of sY1192 (61.5%, 48/78); the common deletion of sY1192 and sY153 (1.3%, 1/78); the common deletion of sY1192, sY153, sY254, and sY255 (26.9%, 21/78); the common deletion of sY1192, sY121, sY127, and sY134 (1.3%, 1/78); the common deletion of sY1192, sY121, sY127, sY134, sY153, sY254, and sY255 (1.3%, 1/78); the common deletion of sY1192, sY121, sY127, sY134, sY153, sY254, sY255, and sY160 (3.8%, 3/78); the common deletion of sY1192, sY105, sY121, sY134, sY152, sY153, sY254, sY255, and sY160 (1.3%, 1/78); and 15 missing loci (2.6%, 2/78). The sperm detection rate was similar in the semen of patients with sY1192 independent deletion and sY1192 combined deletion (52.1% vs. 50.0%, P > 0.05). The sperm detection rate was higher than that in other types of microdeletions present at the sY1192 locus (52.1% vs. 32.0%, P < 0.05). The hormone levels were similar in patients with sY1192 deletion alone and in those with sY1192 deletion and other types of microdeletions in the presence of the sY1192 locus (P > 0.05), but the Follicle stimulating hormone (FSH), Luteinizing hormone (LH), Estradiol (E2),andTestosterone (T) were higher than those in the normal human controls (P < 0.05). After multiple intracytoplasmic sperm injection (ICSI) techniques, the total pregnancy rate of sY1192 independent deletion was similar to that of other types of microdeletions (73.9% vs. 75.0%, P > 0.05), but the fertilization rate and cleavage rate were higher (P < 0.05).
Conclusions: Eight deletion patterns were observed for sY1192 microdeletions of AZFb/c, dominated by the independent deletion of sY1192. Combined deletions mostly occurred in sY1192, sY153, sY254, and sY255 (the b2–b4 amplicon region distributed in the AZFc region). The FSH, T, E2, and LH levels in patients with sY1192 deletions were higher than those in normal subjects and were not different from other types of microdeletions. After ICSI, the fertilization rate and cleavage rate of the sY1192 independent microdeletion were higher than those of other Y chromosome microdeletion types, but there was no difference in pregnancy outcomes.