title: Male-specific DNA markers provide genetic evidence of an XY chromosome system, a recombination arrest and allow the tracing of paternal lineages in date palm.
abstract: Whether sex chromosomes are differentiated is an important aspect of our knowledge of dioecious plants, such as date palm (Phoenix dactylifera). In this crop plant, the female individuals produce dates, and are thus the more valuable sex. However, there is no way to identify the sex of date palm plants before reproductive age, and the sex-determining mechanism is still unclear. To identify sex-linked microsatellite markers, we surveyed a set of 52 male and 55 female genotypes representing the geographical diversity of the species. We found three genetically linked loci that are heterozygous only in males. Male-specific alleles allowed us to identify the gender in 100% of individuals. These results confirm the existence of an XY chromosomal system with a nonrecombining XY-like region in the date palm genome. The distribution of Y haplotypes in western and eastern haplogroups allowed us to trace two male ancestral paternal lineages that account for all known Y diversity in date palm. The very low diversity associated with Y haplotypes is consistent with clonal paternal transmission of a nonrecombining male-determining region. Our results establish the date palm as a biological model with one of the most ancient sex chromosomes in flowering plants.
authors.affiliation: IRD/CIRAD Palm Developmental Biology Group, UMR DIADE, Centre IRD, 911 avenue Agropolis, 34394, Montpellier, France.|Laboratoire de Génétique Moléculaire, Immunologie et Biotechnologie, Faculté des sciences de Tunis, Université Tunis El Manar, Campus Universitaire, 2092, El Manar, Tunisia.
authors.forename: Emira
authors.initials: E
authors.lastname: Cherif
authors.affiliation: Laboratoire de Génétique Moléculaire, Immunologie et Biotechnologie, Faculté des sciences de Tunis, Université Tunis El Manar, Campus Universitaire, 2092, El Manar, Tunisia.
authors.forename: Salwa
authors.initials: S
authors.lastname: Zehdi
authors.affiliation: IRD/CIRAD Palm Developmental Biology Group, UMR DIADE, Centre IRD, 911 avenue Agropolis, 34394, Montpellier, France.
authors.forename: Karina
authors.initials: K
authors.lastname: Castillo
authors.affiliation: IRD/CIRAD Palm Developmental Biology Group, UMR DIADE, Centre IRD, 911 avenue Agropolis, 34394, Montpellier, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Chabrillange
authors.affiliation: ISV/CERD, route de l'Aéroport, BP 486, Djibouti, Djibouti.
authors.forename: Sabira
authors.initials: S
authors.lastname: Abdoulkader
authors.affiliation: Dynadiv, UMR DIADE, Centre IRD, 911 avenue Agropolis, 34394, Montpellier, France.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Pintaud
authors.affiliation: INRA, UMR 1334 Amélioration Génétique et Adaptation des Plantes (AGAP), 34398, Montpellier, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Santoni
authors.affiliation: Laboratoire de Génétique Moléculaire, Immunologie et Biotechnologie, Faculté des sciences de Tunis, Université Tunis El Manar, Campus Universitaire, 2092, El Manar, Tunisia.
authors.forename: Amel
authors.initials: A
authors.lastname: Salhi-Hannachi
authors.affiliation: Institut des Sciences de l'Evolution de Montpellier, Unité Mixte de Recherche 5554, Centre National de la Recherche Scientifique, Université Montpellier 2, 34095, Montpellier, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Glémin
authors.affiliation: IRD/CIRAD Palm Developmental Biology Group, UMR DIADE, Centre IRD, 911 avenue Agropolis, 34394, Montpellier, France.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Aberlenc-Bertossi
mesh_terms: D000483:Alleles; D028023:Arecaceae / Q000235:genetics*; D032461:Chromosomes, Plant / Q000235:genetics*; D018744:DNA, Plant / Q000235:genetics*; D019143:Evolution, Molecular; D056426:Genetic Loci / Q000235:genetics; D005819:Genetic Markers; D014644:Genetic Variation; D006239:Haplotypes / Q000235:genetics; D018895:Microsatellite Repeats / Q000235:genetics; D010802:Phylogeny; D011995:Recombination, Genetic
chemical_list: D018744:DNA, Plant; D005819:Genetic Markers