Purpose: This study aims to characterize the origin of testicular post-meiotic cells in non-mosaic Klinefelter's syndrome (KS).
Methods: The study included testicular tissue specimens from 11 non-mosaic KS patients, with (6 positive) and without (5 negative) spermatozoa presence. The obtained testicular cells were affixed and stained for morphology followed by fluorescence in situ hybridization (FISH) for centromeric probes X, Y, and 18. We used a computerized automated cell scanning system that enables simultaneous viewing of morphology and FISH in the same cell.
Results: A total of 12,387 cells from the positive cases, 11,991 cells from the negative cases, and 1,711 cells from the controls were analyzed. The majority of spermatogonia were 47, XXY in both the positive and negative KS cases (88.9 ± 4.76 % and 90.6 ± 4.58 %) as were primary spermatocytes (76.8 ± 8.14 % and 79.6 ± 7.30 %). The respective rates of secondary spermatocytes and post-meiotic cells (round, elongating spermatids and sperm cells) were 1.1 ± 1.39 % in the positive cases, 2.9 ± 3.33 % in the negative cases, compared to 67.6 ± 6.22 % in the controls (P < 0.02). Pairing of both 18 and XY homologous chromosomes in 46,XY primary spermatocytes was 2.5 ± 2.31 % and 3.4 ± 2.39 %, respectively, compared to 19.8 ± 8.95 % in the control group (P < 0.02) and in 47,XXY primary spermatocytes in 2.4 ± 3.8 % in the positive group and 3.2 ± 2.26 % in the negative group.
Conclusions: This study presents data to indicate that the majority of primary spermatocytes in the testes of non-mosaic KS patients are 47,XXY and could possibly develop into post-meiotic cells.