Arctic char (Salvelinus alpinus) and brook trout (Salvelinus fontinalis) hybridize and their offspring is viable and fertile. This may be a real treat for the native European stocks of Arctic char which gene pools might be unintendedly contaminated with the genetic elements of brook trout. On the other hand, hybrids of these two species are appreciated by customers and have some potential for the aquaculture. Moreover, Salvelinus hybrids and backcross individuals are interesting models in the research focused on influence of hybridization on the genomic organization and chromosome rearrangements. Thus, the main goal of the present study was to examine chromosomes of Arctic char × brook trout F₁, F₂ hybrids and backcross individuals and compare with genomic information concerning parental species to recognize karyotypic changes provoked by the hybridization events. Application of conventional and molecular (FISH) techniques allow to identify characteristic chromosomes for both parental species in the hybrid progeny and show multiplicity of cytotypes among different types of crosses with variability in structure and number of chromosome (81–85) and chromosome arm (99–101). Chromosome fragment was detected in the karyotype of one F₁ and one backcross individual and the presence of one triploid (3n) fish was documented. Occurrence of chromosomes containing internally located telomeric sequences (ITS) inherited after brook trout or both parental species was shown in F₁ and backcross progeny. Moreover, additional CMA₃-positive signal on chromosome from Arctic char pair no. 2 in F₁ fish and interstitially located active NOR visible on subtelo-acrocentric (F₂ hybrid) and acrocentric (Sf × H individual) chromosomes were detected. Described polymorphic chromosomes together with specific, interstitial location of CMA₃-positive found in F₂ and Sf × H hybrids and DAPI-positive regions observed in H × Sa fish at different uniarmed chromosomes pair presumably are remnants of chromosomal rearrangements. Provided results strongly indicate that the hybridization process influenced the genome organization in the Salvelinus hybrid progeny.

北极红点鲑 ( Salvelinus alpinus ) 和溪鳟鱼 ( Salvelinus fontinalis ) 杂交，它们的后代可以生育和繁殖。这对欧洲本土北极红点鲑种群来说可能是一种真正的享受，它们的基因库可能会无意中被鳟鱼的遗传元素污染。另一方面，这两个品种的杂交品种受到客户的青睐，具有一定的水产养殖潜力。此外，Salvelinus杂种和回交个体是研究中有趣的模型，重点是杂交对基因组组织和染色体重排的影响。因此，本研究的主要目标是检查北极红点鲑×鳟鱼 F ₁ , F _{2 的}染色体杂交和回交个体，并与有关亲本物种的基因组信息进行比较，以识别由杂交事件引起的核型变化。常规和分子 (FISH) 技术的应用允许识别杂交后代中亲本物种的特征染色体，并显示不同类型杂交之间的细胞型多样性，染色体结构和数量（81-85）和染色体臂（99） –101）。在一个 F ₁和一个回交个体的核型中检测到染色体片段，并记录了一条三倍体 (3n) 鱼的存在。F _{1 中}显示了在鳟鱼或两个亲本物种之后遗传的含有内部定位端粒序列 (ITS) 的染色体的出现和回交后代。此外，来自北极炭对编号的染色体上的额外 CMA ₃阳性信号。检测到 F ₁鱼中的2和间质定位的活性 NOR，在近端着丝粒（F ₂杂种）和近端着丝粒（Sf × H 个体）染色体上可见。所描述的多态性染色体连同在 F ₂和 Sf × H 杂种中发现的 CMA ₃阳性的特定间隙位置以及在不同单臂染色体对的 H × Sa 鱼中观察到的 DAPI 阳性区域可能是染色体重排的残余。提供的结果强烈表明杂交过程影响了Salvelinus杂交后代的基因组组织。