Nonhomologous associations of C-heterochromatin at human male meiotic prophase

In human male meiotic prophase, nonhomologous pairings and connections between C-heterochromatic regions were demonstrated by C-banding and G-l 1 staining. Approximately 40% of the pachytene stages exhibited bivalent associations at regions of C-heterochromatin. Nonhomologous associations were seen between all possible morphological types of bivalents. Evidence is submitted suggesting that nonhomologous associations between regions of C-heterochromatin are a fairly common event in many organisms, including man, and the possible roles of this phenomenon in meiosis are discussed.