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Chromosome Studies in Hypoptopomatinae (Pisces, Siluriformes, Loricariidae): L. XX/XY Sex Chromosome Heteromorphism in Pseudotocinclus tietensis
(1992-01-01)
The cytogenetic analysis of 13 specimens (9 males and 4 females) of Pseudotocinclus tietensis showed that this species has 2n=54 chromosomes (26M+20SM+6ST) plus one heteromorphic pair (SM/M) in the males and one homomorphic ...
Morphologically differentiated sex chromosomes in neotropical freshwater fish
(2001-12-01)
A general survey of the occurrence of morphologically differentiated sex chromosomes in the neotropical freshwater fishes is presented. The total number of 32 occurrences involving simple XX-XY and ZZ-ZW, and multiple ...
Neo-xy sex chromosomes in zygoclistron nasicum (Orthoptera-acridoidea)
(1979-01-01)
The karyotype of Z. nasicum is described. It consists of 2n=20 ♂ (XY)-20 ♀ (XX), with a pair of large metacentric autosomes, a metacentric X and an acrocentric Y, the remaining autosomes being acrocentric. Both the metacentric ...
Chimerism 47,XY,+21/46,XX in a female infant with anencephaly and other congenital defects
(Sociedade Brasileira de Genética, 2006)
An abnormal terminal X-Y interchange accounts for most but not all cases of human XX maleness
(1987)
To determine if human XX maleness results from an abnormal chromosomal X-Y interchange, we studied the inheritance of the paternal pseudoautosomal region in nine patients. Those six patients in whom Y-specific DNA was found ...
Comparative chromosomal analyses in species of the genus Pimelodella (Siluriformes, Heptapteridae): occurrence of structural and numerical polymorphisms
(UNIV FLORENCE BOTANY INST, 2010)
Cytogenetic analyses were carried out in five species of Pimelodella from the main sub-basins of Upper Parana River and Paraiba do Sul River. The diploid number ranged from 2n = 46 to 2n = 58 chromosomes, and all populations ...
Sex chromosomes and internal telomeric sequences in dormitator latifrons (Richardson 1844) (eleotridae: Eleotrinae): An insight into their origin in the genus
(2020-06-01)
The freshwater fish species Dormitator latifrons, commonly named the Pacific fat sleeper, is an important food resource in CentralSouth America, yet almost no genetic information on it is available. A cytogenetic analysis ...
Evidence of an XX/XY sex chromosome system in the fish Dormitator maculatus (Teleostei, Eleotrididae)
(Sociedade Brasileira de Genética, 2006-01-01)
The fish Dormitator maculatus has a chromosomes number of 2n = 46, females having a karyotype of 14 M, 28 SM, 2 ST and 2A and males 13 M, 28 SM, 3 ST and 2A. The presence of a heteromorphic pair in the males and a corresponding ...