Hum. Reprod. Advance Access originally published online on April 21, 2005
Human Reproduction 2005 20(8):2168-2172; doi:10.1093/humrep/dei034
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cytogenetic, molecular and testicular tissue studies in an infertile 45,X male carrying an unbalanced (Y;22) translocation: Case report
1 Service de Génétique et Reproduction and 2 Service de Gynécologie-Obstétrique, Hôpital Antoine Béclère, 92140 Clamart, 3 Service d'Urologie-Andrologie, 4 Laboratoire d'Hormonologie et de Biologie Moléculaire, 5 Service d'Anatomie et Cytologie Pathologiques and 6 Laboratoire de Biologie Andrologique, Hôpital Bicêtre, 94270 Le Kremlin Bicêtre, France
7 To whom correspondence should be addressed at: Service de Biologie et Génétique de la Reproduction, Hôpital Antoine Béclère, 157, rue de la Porte de Trivaux, 92140 Clamart, France. Email: sophie.brisset{at}abc.ap-hop-paris.fr
 |
Abstract |
|---|
 Top Abstract IntroductionCase reportDiscussionReferences |
|---|
(Y;autosome) translocations have been reported in association with male infertility. Different mechanisms have been suggested to explain the male infertility, such as deletion of the azoospermic factor (AZF) on the long arm of the Y chromosome, or meiosis impairment. We describe a new case with a de novo unbalanced translocation t(Y;22) and discuss the genotype–phenotype correlation. A 36 year old male with azoospermia was found to have a mosaic 45,X/46,X, + mar karyotype. Fluorescence in situ hybridization (FISH) showed the presence of a derivative Y chromosome containing the short arm, the centromere and a small proximal part of the long-arm euchromatin of the Y chromosome and the long arm of chromosome 22. The unstable small marker chromosome included the short arm and the centromere of chromosome 22. This unbalanced translocation t(Y;22)(q11.2;q11.1) generated the loss of the long arm of the Y chromosome involving a large part of AZFb, AZFc and Yq heterochromatin regions. Testicular tissue analyses showed sperm in the wet preparation. Our case shows the importance of documenting (Y;autosome) translocations with molecular and testicular tissue analyses.
Key words: AZF deletions/azoospermia/genotype–phenotype correlation/testicular biopsy/(Y;autosome) translocation
|
Introduction |
|---|
|
TopAbstractIntroductionCase reportDiscussionReferences |
|---|
Azoospermia, when no sperm can be detected on two separate semen samples, is found in up to 10–20% of infertile men (Jarow et al., 1989
). Genital tract obstruction and defective spermatogenesis are the principal causes of azoospermia (Jarow et al., 1989). Chromosome aberration is a well-known factor influencing spermatogenesis. Chromosomal abnormalities are present in 7% of infertile men and in 10–15% of azoospermic men (De Braekeleer and Dao, 1991; Van Assche et al., 1996). Among the karyotypic abnormalities found in azoospermic men, sex chromosome abnormalities predominate (mainly 47,XXY genotype). Also, azoospermia may be due to structural abnormalities of the chromosomes. Translocations involving Y chromosome have been reported in association with male infertility (Hsu, 1994). Two possible mechanisms can explain the male infertility. First, the azoospermic factor (AZF), which is critical for spermatogenesis, is located on Yq11 euchromatin and may be affected secondary to a microdeletion, rearrangement or complete loss as a result of the translocation mechanism (Vogt et al., 1996). This mechanism is quite improbable when no deletion loss of AZF loci is observed (Delobel et al., 1998; Pabst et al., 2002) or when the breakpoint on Y chromosome is distal to Yq11 (Delobel et al., 1998; Buonadonna et al., 2002). Thus, a second explanation could be a defective X–Y pairing during meiosis with an abnormal sex vesicle formation and consequently a spermatogenetic arrest (Laurent et al., 1982; Delobel et al., 1998; Buonadonna et al., 2002). We describe here a new case with a de novo unbalanced translocation t(Y;22)(q11.2;q11.1) in an infertile man associated with sperm production. |
Case report |
|---|
|
TopAbstractIntroductionCase reportDiscussionReferences |
|---|
Clinical report
The patient was referred to our centre for infertility investigations. The patient had absolute azoospermia. No sperm were found in any of the three routine semen analyses. The patient was an apparently healthy 36 year old male. His physical examination was normal, except for a slight testicular hypotrophy (11 and 8 ml). The family history was unremarkable. The elevated serum FSH concentration of 18 IU/l (normal range 3–7) and LH serum concentration of 11 IU/l (normal range 3–8) suggested abnormal spermatogenesis. Free testosterone level (280 ng/dl, normal range 450–950) and inhibin B level (24 pg/ml, normal range 80–270) were low.
Conventional cytogenetic analysis
Chromosome analyses were performed on cultured lymphocytes. Standard techniques were used for the preparation of metaphase spreads. The constitutional karyotype was established after R banding.
Fluorescence in situ hybridization (FISH)
FISH analyses were performed on lymphocyte metaphase spreads from the patient using standard protocols. The following DNA probes were used for FISH analysis: X chromosome (DXZ1), Y chromosome (DYZ3) and chromosome 14/22 (D14Z1/D22Z1) centromeric specific probes, whole chromosome painting probes for chromosome 22 and Y chromosome and DiGeorge N25 chromosome region probe (Vysis, USA).
Molecular analysis
DNA was extracted from blood lymphocytes. Microdeletion analysis of the Y chromosome was performed using a sequence-tagged site (STS)–PCR approach. Twenty-eight STS corresponding to the three distinct AZF loci were selected. The STS tested were sY84 for AZFa, sY95, sY97, sY169, sY102, sY105, sY109 for the interval between AZFa and AZFb, sY113, sY115, sY117, sY124, sY130, sY134, sY136, sY143, sY142 for AZFb, sY152, sY232, sY156, sY240, sY148, sY249, sY204, sY208, sY254, sY269, sY158 for AZFc, and sY160 for the heterochromatic distal Yq region.
Testicular tissue analyses
Fresh testicular tissue was obtained surgically from the patient. Direct cytological examination and histological examination were performed on testicular tissue.
Immediately after testicular biopsy, the extracted testicular seminiferous tubules were deposited on a sterile glass slide and gently dissected with sterile microscissors in FertiCult medium (Izard et al., 1999). The wet preparation of the suspension was then checked for the presence of sperm under a phase-contrast microscope at x400 magnification. The morphology of sperm was assessed using Shorr staining. Sperm morphology was evaluated according to modified David's classification (Auger et al., 2001).
For testicular histology, the biopsy specimen was fixed with AFA (75% alcohol, 0.8% formalin and 5% acetic acid). After embedding with paraffin, tissue sections were cut with a thickness of 4 µm. All sections were stained with haematoxylin, eosin and saffron.
Conventional cytogenetic analysis
The cytogenetic analysis was initially interpreted as a 45,X karyotype. Further cytogenetic examination revealed a mosaic 45,X[15]/46,X, + mar[3] with a small chromosomal marker whose origin could not be resolved by conventional analysis (Figure 1A). The father had a normal karyotype.
|
FISH analysis on lymphocyte metaphases
Two-colour FISH with the X chromosome centromeric (green) and the Y chromosome centromeric (red) specific probes showed the presence of both centromeres. The Y chromosome centromeric specific probe showed that the hybridization signal was located on a chromosome 22 (Figure 1B).
The 14/22 
-satellite centromeric probe showed signals on both centromeres of chromosomes 14, one signal on the centromere of one chromosome 22 and one signal on the centromere of the small chromosome marker. This suggested that the small marker chromosome included the centromere of one chromosome 22 (Figure 1C).
Two-colour FISH with paint specific probes for Y chromosome (green) and chromosome 22 (red) showed a derivative Y chromosome containing the short arm, the centromere and a small proximal part of the long-arm euchromatin of the Y chromosome and the long arm of a chromosome 22. Thus, the small marker chromosome represented a part of the translocation event corresponding to the short arm and the centromere of chromosome 22 (Figure 1D). On chromosome 22, the breakpoint occurred in the region just below the centromere as confirmed by FISH using the DiGeorge locus probe. This probe hybridized on both chromosome 22 and derivative Y chromosome, indicating therefore that the breakpoint on chromosome 22 was located between centromere and 22q11.2 region (data not shown).
The results of these hybridization experiments indicated therefore that the patient was a carrier of an unbalanced translocation t(Y;22)(q11.2;q11.1) (Figure 2).
|
Molecular analysis
STS sY84, sY95, sY97, sY169, sY102, sY105, sY109 gave positive results. The other STS sY113, sY115, sY117, sY124, sY130, sY134, sY136, sY143, sY142, s152, sY232, sY156, sY240, sY148, sY249, sY204, sY208, sY254, sY269, sY158 and sY160 were not amplified. Thus, the breakpoint on Y chromosome was located between sY109 (proximal to AZFb) and sY113 (proximal border of AZFb).
Testicular tissue analyses
A wet preparation of the testicular tissue sample showed the presence of non-motile sperm. Shorr staining showed a normal morphology (the normal morphology rate was 34%) (Figure 3).
|
The testis histology was analysed in a series of tissue serial sections obtained by testicular biopsies. Histopathological examination showed atrophic and hyalinized tubules with Sertoli cells and few Leydig cells. Neither germ cells nor sperm were observed. Thus the testis histology was interpreted as a Sertoli cell-only syndrome (SCOS).
|
Discussion |
|---|
|
TopAbstractIntroductionCase reportDiscussionReferences |
|---|
We describe here a new case of an unbalanced de novo t(Y;22) translocation in an azoospermic male. This (Y;22) translocation was diagnosed initially as a 45,X conventional karyotype. A male phenotype in the presence of a 45,X chromosome constitution represents a rare and generally unexplained condition. Some of these cases are in fact low-grade 45,X/46,XY mosaics overlooked by routine cytogenetic analysis. Another explanation for a 45,X karyotype is an undiagnosed (Y;autosome) translocation. In our case, a part of the long arm of one chromosome 22 has been translocated onto Y chromosome at band Yq11.1. Because the morphology of the derivative Y chromosome was similar to the morphology of the normal chromosome 22, this translocation was not initially detected. Moreover, the small marker was not easy to detect in conventional analysis due to its small size and was seen more easily with DAPI staining.
(Y;autosome) translocations have been associated with normal and abnormal spermatogenesis. Hsu (1994) reviewed over 130 cases of (Y;autosome) translocations. In the most common form, the heterochromatic region of Yq (Yqh or Yq12) is translocated onto the short arm of an acrocentric chromosome (D or G group chromosome). Other types of (Y;autosome) translocation include balanced and unbalanced reciprocal translocations. A chromosomal breakpoint at band Yq11, as observed in our case, is rarely described. Twenty cases of adult males carrying a (Y;autosome) translocation with a breakpoint at Yq11 region are reviewed in Table I. Since the phenotype may depend on the localization of the Yq breakpoint and on the nature of Yq material lost, it is of great interest to ascertain the Yq breakpoint by DNA molecular studies (AZF screening or interval deletions studies). Deletions of the AZFa, b and c regions are associated with abnormal spermatogenesis from SCOS to hypospermatogenesis (Vogt et al., 1996; Krausz et al., 2003; Simoni et al., 2004).
|
Our patient had absolute azoospermia. We decided to perform a testicular biopsy to increase the chances for retrieving viable sperm. Several authors have studied the success rate of testicular sperm retrieval in men with Y deletions (Brandell et al., 1998
; Silber et al., 1998; Krausz et al., 2000; Hopps et al., 2003; Simoni et al., 2004; Vogt, 2004). It has been shown in these studies that a proportion of patients with AZFc deletion may have sperm retrievable within the testis. Deletions involving the AZFb regions are generally associated with a poor prognosis for sperm retrieval. The probability of finding sperm in a patient with a complete AZFb deletion is virtually nil. However, a diagnosis of partial AZFb deletion is compatible with sperm retrieval. No sperm have been found in the testes of azoospermic men with AZFb + c deletions. We present here a new case with an unbalanced translocation t(Y;22) which generated the loss of the long arm of the Y chromosome involving a large part of AZFb, AZFc and Yq heterochromatin regions and with sperm seen in the testis biopsy. However, our STS analysis is not sufficient to precisely characterize the extent of the deletion. The only way to demonstrate that a complete AZFb deletion has occurred in this specific case would be a sequencing approach since rearrangements interfering with AZFb region sequences cannot be excluded in a translocated Y chromosome. Unfortunately this is not available in our case. The sperm could thereafter be used for ICSI in combination with preimplantation genetic diagnosis. The chromosomal risks of this translocation in offspring are aneuploidy of chromosome 22 and sex numerical anomalies. Nevertheless, the most important genetic risk for the couple concerns sex chromosome anomalies because monosomy or trisomy 22 are not viable.
In conclusion, our case highlights the importance of documenting (Y;autosome) translocations with molecular and testicular tissue analyses in order to establish a genotype–phenotype correlation.
|
References |
|---|
|
TopAbstractIntroductionCase reportDiscussionReferences |
|---|
Abeliovich D, Potashnik G, Dar H, Lugasi N and Rave D (1986) Chromosomal rearrangements in three infertile men. Andrologia 18, 147–151.[Web of Science][Medline]
Andersson M, Page DC, Pettay D, Subrt I, Turleau C, de Grouchy J and de la Chapelle A (1988) Y;autosome translocations and mosaicism in the aetiology of 45,X maleness: assignment of fertility factor to distal Yq11. Hum Genet 79, 2–7.[CrossRef][Web of Science][Medline]
Arnemann J, Schnittger S, Hinkel GK, Tolkendorf E, Schmidtke J and Hansmann I (1991) A sterile male with 45,X0 and a Y;22 translocation. Hum Genet 87, 134–138.[CrossRef][Web of Science][Medline]
Auger J, Eustache F, Andersen AG, Irvine DS, Jorgensen N, Skakkebaek NE, Suominen J, Toppari J, Vierula M and Jouannet P (2001) Sperm morphological defects related to environment, lifestyle and medical history of 1001 male partners of pregnant women from four European cities. Hum Reprod 16, 2710–2717.
Bardoni B, Zuffardi O, Guioli S, Ballabio A, Simi P, Cavalli P, Grimoldi MG, Fraccaro M and Camerino G (1991) A deletion map of the human Yq11 region: implications for the evolution of the Y chromosome and tentative mapping of a locus involved in spermatogenesis. Genomics 11, 443–451.[Web of Science][Medline]
Brandell RA, Mielnik A, Liotta D, Ye Z, Veeck LL, Palermo GD and Schlegel PN (1998) AZFb deletions predict the absence of spermatozoa with testicular sperm extraction: preliminary report of a prognostic genetic test. Hum Reprod 13, 2812–2815.
Buonadonna AL, Cariola F, Caroppo E, Di Carlo A, Fiorente P, Valenzano MC, D'Amato G and Gentile M (2002) Molecular and cytogenetic characterization of an azoospermic male with a de-novo Y;14 translocation and alternate centromere inactivation. Hum Reprod 17, 564–569.
Callen DF, Sutherland GR and Carter RF (1987) A fertile man with tdic(Y;22): how a stable neo-X1X2Y sex-determining mechanism could evolve in man. Am J Med Genet Suppl 3, 151–155.[CrossRef][Medline]
De Braekeleer M and Dao TN (1991) Cytogenetic studies in male infertility: a review. Hum Reprod 6, 245–250.
Delobel B, Djlelati R, Gabriel-Robez O, Croquette MF, Rousseaux-Prevost R, Rousseaux J, Rigot JM and Rumpler Y (1998) Y-Autosome translocation and infertility: usefulness of molecular, cytogenetic and meiotic studies. Hum Genet 102, 98–102.[CrossRef][Web of Science][Medline]
Dutrillaux B and Gueguen J (1975) Mitotic and meiotic analysis of an Y-autosome translocation. Humangenetik 27, 241–245.[CrossRef][Web of Science][Medline]
Faed MJ, Lamont MA and Baxby K (1982) Cytogenetic and histological studies of testicular biopsies from subfertile men with chromosome anomaly. J Med Genet 19, 49–56.
Gal A, Weber B, Neri G, Serra A, Muller U, Schempp W and Page DC (1987) A 45,X male with Y-specific DNA translocated onto chromosome 15. Am J Hum Genet 40, 477–488.[Web of Science][Medline]
Giltay JC, Tiemessen CH, van Inzen WG and Scheres JM (1998) One normal child and a chromosomally balanced/normal twin after intracytoplasmic sperm injection in a male with a de-novo t(Y;16) translocation. Hum Reprod 13, 2745–2747.
Giltay JC, Kastrop PM, Tiemessen CH, van Inzen WG, Scheres JM and Pearson PL (1999) Sperm analysis in a subfertile male with a Y;16 translocation, using four-color FISH. Cytogenet Cell Genet 84, 67–72.[CrossRef][Web of Science][Medline]
Gonzales J, Lesourd S and Dutrillaux B (1981) Mitotic and meiotic analysis of a reciprocal translocation t(Y;3) in an azoospermic male. Hum Genet 57, 111–114.[Web of Science][Medline]
Hopps CV, Mielnik A, Goldstein M, Palermo GD, Rosenwaks Z and Schlegel PN (2003) Detection of sperm in men with Y chromosome microdeletions of the AZFa, AZFb and AZFc regions. Hum Reprod 18, 1660–1665.
Hsu LY (1994) Phenotype/karyotype correlations of Y chromosome aneuploidy with emphasis on structural aberrations in postnatally diagnosed cases. Am J Med Genet 53, 108–140.[CrossRef][Web of Science][Medline]
Izard V, Marmor D, Peron A, Paradis V, Benoit G, Soufir JC and Jardin A (1999) Cytological evaluation of germinal populations as part of a testicular sperm retrieval strategy. In Hamamah S, Mieusset R, Olivennes F, and Frydman R (eds) Male Sterility and Motility Disorders. Etiological Factors and Treatment. Serono Symposia, Norwell, USA, pp. 253–258.
Jarow JP, Espeland MA and Lipshultz LI (1989) Evaluation of the azoospermic patient. J Urol 142, 62–65.[Web of Science][Medline]
Krausz C, Quintana-Murci L and McElreavey K (2000) Prognostic value of Y deletion analysis: what is the clinical prognostic value of Y chromosome microdeletion analysis? Hum Reprod 15, 1431–1434.
Krausz C, Forti G and McElreavey K (2003) The Y chromosome and male fertility and infertility. Int J Androl 26, 70–75.[CrossRef][Web of Science][Medline]
Laurent C and Dutrillaux B (1976) Translocation t(Y;14) in an azoospermic man. Ann Genet 19, 207–209.[Web of Science][Medline]
Laurent C, Chandley AC, Dutrillaux B and Speed RM (1982) The use of surface spreading in the pachytene analysis of a human t (Y;17) reciprocal translocation. Cytogenet Cell Genet 33, 312–318.[Web of Science][Medline]
Pabst B, Glaubitz R, Schalk T, Schneider U, Schulze W and Miller K (2002) Reciprocal translocation between Y chromosome long arm euchromatin and the short arm of chromosome 1. Ann Genet 45, 5–8.[Web of Science][Medline]
Ratomponirina C, Couturier J, Gabriel-Robez O, Rumpler Y, Dutrillaux B, Croquette M, Rabache Q and Leduc M (1985) Aberrations of the synaptonemal complexes in a male 46,XY,-14, + der(14)t(Y;14). Ann Genet 28, 214–218.[Web of Science][Medline]
Sasagawa I, Nakada T, Adachi Y, Kato T, Sawamura T, Ishigooka M and Hashimoto T (1993) Y-autosome translocation associated with azoospermia. Scand J Urol Nephrol 27, 285–288.[Web of Science][Medline]
Schempp W, Weber B, Serra A, Neri G, Gal A and Wolf U (1985) A 45,X male with evidence of a translocation of Y euchromatin onto chromosome 15. Hum Genet 71, 150–154.[Web of Science][Medline]
Silber SJ, Alagappan R, Brown LG and Page DC (1998) Y chromosome deletions in azoospermic and severely oligozoospermic men undergoing intracytoplasmic sperm injection after testicular sperm extraction. Hum Reprod 13, 3332–3337.
Simoni M, Bakker E and Krausz C (2004) EAA/EMQN best practice guidelines for molecular diagnosis of Y-chromosomal microdeletions. State of the art 2004. Int J Androl 27, 240–249.[CrossRef][Web of Science][Medline]
Smith A, Fraser IS and Elliott G (1979) An infertile male with balanced Y;19 translocation. Review of Y;autosome translocations. Ann Genet 22, 189–194.[Web of Science][Medline]
Subrt I and Blehova B (1974) Robertsonian translocation between the chromosome Y and 15. Humangenetik 23, 305–309.[CrossRef][Web of Science][Medline]
Teyssier M, Rafat A and Pugeat M (1993) Case of (Y;1) familial translocation. Am J Med Genet 46, 339–340.[CrossRef][Web of Science][Medline]
Turleau C, Chavin-Colin F and de Grouchy J (1980) A 45,X male with translocation of euchromatic Y chromosome material. Hum Genet 53, 299–302.[Web of Science][Medline]
Van Assche E, Bonduelle M, Tournaye H, Joris H, Verheyen G, Devroey P, Van Steirteghem A and Liebaers I (1996) Cytogenetics of infertile men. Hum Reprod 11 (Suppl 1), 1–24.
Vogt PH (2004) Genomic heterogeneity and instability of the AZF locus on the human Y chromosome. Mol Cell Endocrinol 224, 1–9.[CrossRef][Web of Science][Medline]
Vogt PH, Edelmann A, Kirsch S, Henegariu O, Hirschmann P, Kiesewetter F, Kohn FM, Schill WB, Farah S, Ramos C et al (1996) Human Y chromosome azoospermia factors (AZF) mapped to different subregions in Yq11. Hum Mol Genet 5, 933–943.
Submitted on September 16, 2004; resubmitted on March 22, 2005; accepted on March 31, 2005.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  A. Perrin, N. Douet-Guilbert, M.J. Le Bris, G. Keromnes, M.L. Langlois, P. Barriere, J. Amice, V. Amice, M. De Braekeleer, and F. Morel Segregation of chromosomes in sperm of a t(X;18)(q11;p11.1) carrier inherited from his mother: Case Report Hum. Reprod., January 1, 2008; 23(1): 227 - 230. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A.K. Faure, I. Aknin-Seifer, V. Satre, F. Amblard, F. Devillard, S. Hennebicq, J. Chouteau, U. Bergues, R. Levy, and S. Rousseaux Fine mapping of re-arranged Y chromosome in three infertile patients with non-obstructive azoospermia/cryptozoospermia Hum. Reprod., July 1, 2007; 22(7): 1854 - 1860. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||