<abstract xmlns="http://www.w3.org/1999/xhtml">

<sec><h3>Introduction</h3>
<p>Robertsonian translocation (RobT) is the central fusion of the long arms of two acrocentric chromosomes, leading to 45 chromosomes in humans. The most common ones are rob(13;14) and rob(14;21) (91%). Other types of RobT are so-called rare cases. In the general population RobTs occur with a frequency of approximately 0.123%, but among men with reproductive failure this value rises 9-fold. Infertility in RobT carriers is associated with the formation of unbalanced spermatozoa resulting from segregation of the chromosomes involved in trivalent during the meiotic prophase. In spermatozoa of many RobT carriers an increased level of chromosomal aneuploidy is observed.</p>
</sec>
<sec><h3>Materials and Methods</h3>
<p>We examined the hyperhaploidy level of chromosomes 7, 9, 18, 21, 22, X and Y in spermatozoa of 6 RobT unrelated carriers: two carriers with rare rob(13;15), one with rare rob(13;22), and three of the common rob(13;14). Results were compared with the control data from a group of 7 fertile men with a normal karyotype. Fluorescent <italic>in situ</italic> hybridization (FISH) was applied.</p>
</sec>
<sec><h3>Results</h3>
<p>We found an increased level of sperm aneuploidy regarding at least one of the analyzed chromosomes in each of the carriers, while in rare RobTs interchromosomal effect (ICE) was observed. Meiotic segregation pattern of a rare rob(13;15) carrier revealed the 76% of normal /balanced spermatozoa.</p>
</sec>
<sec><h3>Disucussion</h3>
<p>Due to the relatively high population frequency of RobTs, their influence on reproductive failure, hight risk of imbalancement in prenatal diagnosis (7%), and small amount of data for rare RobTs, each newly characterized case is valuable in genetic counseling.</p>
</sec>
</abstract>

Introduction
Robertsonian translocation (RobT) is the central fusion of the long arms of two acrocentric chromosomes, leading to 45 chromosomes in humans. The most common ones are rob(13;14) and rob(14;21) (91%). Other types of RobT are so-called rare cases. In the general population RobTs occur with a frequency of approximately 0.123%, but among men with reproductive failure this value rises 9-fold. Infertility in RobT carriers is associated with the formation of unbalanced spermatozoa resulting from segregation of the chromosomes involved in trivalent during the meiotic prophase. In spermatozoa of many RobT carriers an increased level of chromosomal aneuploidy is observed.

Materials and Methods
We examined the hyperhaploidy level of chromosomes 7, 9, 18, 21, 22, X and Y in spermatozoa of 6 RobT unrelated carriers: two carriers with rare rob(13;15), one with rare rob(13;22), and three of the common rob(13;14). Results were compared with the control data from a group of 7 fertile men with a normal karyotype. Fluorescent in situ hybridization (FISH) was applied.

Results
We found an increased level of sperm aneuploidy regarding at least one of the analyzed chromosomes in each of the carriers, while in rare RobTs interchromosomal effect (ICE) was observed. Meiotic segregation pattern of a rare rob(13;15) carrier revealed the 76% of normal /balanced spermatozoa.

Disucussion
Due to the relatively high population frequency of RobTs, their influence on reproductive failure, hight risk of imbalancement in prenatal diagnosis (7%), and small amount of data for rare RobTs, each newly characterized case is valuable in genetic counseling.

Analysis of sperm chromosomes in six carriers of rare and common Robertsonian translocations<xref ref-type="fn" rid="j_01.3001.0014.8122_fn_001a"><sup>*</sup></xref>

Pirogov Russian National Research Medical University

Postępy Higieny i Medycyny Doświadczalnej

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Analysis of sperm chromosomes in six carriers of rare and common Robertsonian translocations

Badanie chromosomów plemnikowych u sześciu nosicieli rzadkich i częstych translokacji Robertsonowskich

Introduction
Robertsonian translocation (RobT) is the central fusion of the long arms of two acrocentric chromosomes, leading to 45 chromosomes in humans. The...

Analysis of sperm chromosomes in six carriers of rare and common Robertsonian translocations^*

Article Category: Original Article

Published Online: Mar 18, 2021

Page range: 199 - 210

Received: Jul 01, 2020

Accepted: Dec 11, 2020

DOI: https://doi.org/10.5604/01.3001.0014.8122

Keywords
rob(13;15), rob(13;22), rob(13;14), sperm aneuploidy, meiotic segregation pattern, rare Robertsonian translocation, RobT

© 2021 Marta Olszewska et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Analysis of sperm chromosomes in six carriers of rare and common Robertsonian translocations*

Article Category: Original Article

Published Online: Mar 18, 2021

Page range: 199 - 210

Received: Jul 01, 2020

Accepted: Dec 11, 2020

DOI: https://doi.org/10.5604/01.3001.0014.8122

Keywordsrob(13;15), rob(13;22), rob(13;14), sperm aneuploidy, meiotic segregation pattern, rare Robertsonian translocation, RobT

© 2021 Marta Olszewska et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Analysis of sperm chromosomes in six carriers of rare and common Robertsonian translocations^*

Keywords
rob(13;15), rob(13;22), rob(13;14), sperm aneuploidy, meiotic segregation pattern, rare Robertsonian translocation, RobT