Small supernumerary marker chromosomes (sSMCs) are a morphologically heterogeneous group of additional structurally abnormal chromosomes that cannot be identified unambiguously by conventional banding techniques alone. Molecular cytogenetic methods enable detailed characterization of sSMCs; however, in many cases interpretation of their clinical significance is problematic. The aim of our study was to characterize precisely sSMCs identified in three patients with dysmorphic features, psychomotor retardation and multiple congenital anomalies. We also attempted to correlate the patients' genotypes with phenotypes by inclusion of data from the literature. The sSMCs were initially detected by G-banding analysis in peripheral blood lymphocytes in these patients and were subsequently characterized using multicolor fluorescence in situ hybridization (M-FISH), (sub)centromere-specific multicolor FISH (cenM-FISH, subcenM-FISH), and multicolor banding (MCB) techniques. Additionally, the sSMCs in two patients were also studied by hybridization to whole-genome bacterial artificial chromosome (BAC) arrays (array-CGH) to map the breakpoints on a single BAC clone level. In all three patients, the chromosome origin, structure, and euchromatin content of the sSMCs were determined. In patient RS, only a neocentric r(2)(q35q36) was identified. It is a second neocentric sSMC(2) in the literature and the first marker chromosome derived from the terminal part of 2q. In the other two patients, two sSMCs were found, as M-FISH detected additional sSMCs that could not be characterized in G-banding analysis. In patient MK, each of four cell lines contained der(4)(:p11.1-->q12:) accompanied by a sSMC(18): r(18)(:p11.2-->q11.1::p11.2-->q11.1:), inv dup(18)(:p11.1-->q11.1::q11.1-->p11.1:), or der(18) (:p11.2-->q11.1::q11.1-->p11.1:). In patient NP, with clinical features of trisomy 8p, three sSMCs were characterized: r(8)(:p12-->q11.1::q11.1-->p21:) der(8) (:p11.22-->q11.1::q11.1-->p21::p21-->p11.22:) and der(21)(:p11.1-->q21.3:). The BAC array results confirmed the molecular cytogenetic results and refined the breakpoints to the single BAC clone resolution. However, the complex mosaic structure of the marker chromosomes derived from chromosomes 8 and 18 could only be identified by molecular cytogenetic methods. This study confirms the usefulness of multicolor FISH combined with whole-genome arrays for comprehensive analyses of marker chromosomes.

Sixteen newly established cell lines with small supernumerary marker chromosomes (sSMC) derived from chromosomes 1, 2, 4, 6, 7, 8, 14, 15, 16, 18, 19, 21, and 22 are reported. Two sSMC are neocentric and derived from 15q24.1-qter and 2q35-q36, respectively. Two further cases each present with two sSMC of different chromosomal origin. sSMC were characterized by multicolor fluorescence in situ hybridization for their chromosomal origin and genetic content. Moreover, uniparental disomy of the sister chromosomes of the sSMC was excluded in all nine cases studied for that reason. The 16 cases provide information to establish a refined genotype-phenotype correlation of sSMC and are available for future studies.

The main aim of the study was to identify differences pertaining to sense of adulthood, exploration, and commitment dimensions between groups of subjects differing in respect of the number of fulfilled adulthood roles and the level of psychosocial maturity. participants and procedureParticipants were 358 individuals aged 18 to 30. Four groups of individuals with different adulthood statuses were designated: (1) immature non-adults (low psychosocial maturity, a small number of adult roles), (2) immature adults (low psychosocial maturity, a large number of adult roles), (3) mature non-adults (high psychosocial maturity, a small number of adult roles), (4) mature adults (high psychosocial maturity, a large number of adult roles). resultsIn the two groups characterized by a high level of psychosocial maturity, sense of adulthood proved to be higher than in the other two groups. Immature adults manifested more visible signs of identity crisis than mature adults, and the pattern of the results in the former group was similar to that observed in the group of immature non-adults and mature non-adults. conclusionsThe studies offer an insight into the relationship between identity of individuals entering adulthood, and social and personal determinants of its formation. The simultaneous analysis of selected psychological and contextual conditionings of identity formation enabled us to obtain valuable results that allow us to formulate the conclusion that both of the spheres mentioned above are important for identity development, and that the most favorable option for identity formation in different areas of young adults' functioning is the joint development of both psychosocial maturity and adult roles. key words commitment; exploration; psychosocial maturity; sense of adulthood; social roles of adulthood; status of adulthood

We present a unique case of a young woman with acute myeloid leukemia (AML) with complex karyotype. The presence of the t(4;11)(q23;p15) is extremely rare in myeloid leukemias, while t(4;8)(q32;q13) has not yet been described in any leukemia reference. Another interesting issue is the familial aggregation of myeloid malignancies and worse course of the disease in each subsequent generation, as well as an earlier onset of the disease. Our report emphasizes the need for thorough pedigree examination upon myeloid malignancy diagnosis as there are relatives for whom counseling, gene testing, and surveillance may be highly advisable.