title: Two Y chromosomes with duplication of the distal long arm including the entire AZFc region.
abstract: Chromosome anomalies/rearrangements of the Y chromosome seldom threaten life and are quite common. The 4.5 Mb AZFc region on Yq11.2 is one of the most polymorphic regions in the human genome. AZFc partial deletion is almost inevitably associated with impaired fertility while the functional significance of AZFc partial duplications remains controversial. In this report, a large Y chromosome with one centromere and two heterochromatic blocks was identified incidentally in two men. The first case was ascertained through surveillance for recurrent miscarriage. The second case was ascertained through amniocytes of a fetus and his father. FISH and array-based comparative genomic hybridization showed duplications of the entire AZFc region as well as Yq euchromatic region. The duplications in Case 1 and Case 2 spanned 4.8 Mb and 6.2 Mb, respectively, of the Yq euchromatic region. These two cases suggest that complete AZFc duplication could be completely benign. It awaits further investigation whether this is a bona fide chromosomal polymorphism.
authors: Cytogenetic Laboratory, Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan.
authors: Hui-Kuo
authors: HK
authors: Hsu
authors: Department of Obstetrics and Gynecology, National Cheng Kung University Hospital and College of Medicine, Tainan, Taiwan.
authors: Mei-Tsz
authors: MT
authors: Su
authors: Department of Genomic Medicine, Center for Medical Genetics, Changhua Christian Hospital, Changhua, Taiwan.
authors: Ming
authors: M
authors: Chen
authors: Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
authors: Pauline
authors: P
authors: Yen
authors: Department of Obstetrics and Gynecology, National Cheng Kung University Hospital and College of Medicine, Tainan, Taiwan. Electronic address: paolink@mail.ncku.edu.tw.
authors: Pao-Lin
authors: PL
authors: Kuo
mesh_terms: D000328:Adult; D002503:Centromere / Q000235:genetics; D041322:Chromosomes, Human, Y / Q000235:genetics*; D005260:Female; D020440:Gene Duplication / Q000235:genetics*; D015894:Genome, Human / Q000235:genetics; D006570:Heterochromatin / Q000235:genetics; D006801:Humans; D008297:Male
chemical_list: D006570:Heterochromatin
keywords: AZF; AZFc region; Duplication; IVF–ET; PAR2; Y chromosome; aCGH; array-based comparative genomic hybridization; azoospermia factor; in vitro fertilization–embryo transfer; pseudoautosomal region 2