Transmission Behavior of B Chromosomes in Prochilodus lineatus (Characiformes, Prochilodontidae)

• Published in: Cytogenetic and genome research Vol. 147; no. 2-3; pp. 179 - 185
• Main Authors: Penitente, Manolo, Daniel, Sandro N., Senhorini, José A., Foresti, Fausto, Porto-Foresti, Fábio
• Format: Journal Article
• Language: English
• Published: Basel, Switzerland 01.01.2015
• Subjects: Animals; Brazil; Breeding - methods; Centromere - genetics; Characiformes - classification; Characiformes - genetics; Chromosomes - genetics; Cytogenetic Analysis; Female; Fisheries - methods; Genetics, Population - methods; Inheritance Patterns; Male; Original Article; Rivers; Species Specificity; Brazil; Mendelian rate; Supernumerary chromosomes; Cytogenetic; Inheritance
• ISSN: 1424-8581; 1424-859X
• DOI: 10.1159/000443384

The population of Prochilodus lineatus found in the Mogi-Guaçu River is karyotypically polymorphic, carrying acrocentric, metacentric, and submetacentric B chromosomes. The analysis of each B chromosome frequency in this species revealed a variation in the distribution pattern, with the metacentric type having the highest frequency (73.30%), followed by submetacentric (25.22%) and acrocentric B chromosomes (1.48%). The transmission pattern of the supernumerary chromosomes was identified by controlled crosses, and it was shown that the acro- and submetacentric B chromosomes have a transmission pattern below the Mendelian rate (k B = 0.333 and k B = 0.385, respectively), but the metacentric variant has a cumulative transmission pattern (k B = 0.587). These results indicate that the acro- and submetacentric B chromosomes are undergoing an extinction process, while the metacentric B chromosomes appear to be accumulating in frequency with each generation.