Genetic discoveries and technological advances have been changing nursing care delivery, which modifies the roles and practices of nursing in society. Although the need for education of nurses in the field of genomics has been recognized in the 1960s, many countries still have no clear guidelines in this field of education and training. The purpose of this study was to evaluate current genomics content in the curriculum of undergraduate and graduate programs of studies in nursing in Croatia, and to measure the genomic literacy of Croatian undergraduate nursing students through assessing participants’ understanding of genomic concepts most critical to nursing practice. The curriculum of undergraduate and graduate programs of nursing classes of 2020/2021 were independently analyzed by the authors. For measuring the knowledge of essential genomic concepts among nurses, a Genomic Nursing Concept Inventory (GNCI^©) instrument was employed. Results indicate that the current genomics content, for undergraduate and graduate nursing programs in Croatia, is inadequate and not concordant among universities. Moreover, the genomic literacy of Croatian undergraduate students (Undergraduate program 10) was found to be low. Scores across respondents ranged from 3 to 22 (out of possible 31), with a mean scale score 9.8 (SD 5.3) (31.6% correct). We can conclude that the curriculum for undergraduate and graduate programs of Studies in nursing should be revised to implement the latest genomic practices and approaches to genomics education while nurses should acquire an adequate level of genomic literacy in order to produce desired outcomes of competency in nursing practice.

Down syndrome (DS, also known as trisomy 21) most often results from chromosomal nondisjunction during oogenesis. Numerous studies sustain a causal link between global DNA hypomethylation and genetic instability. It has been suggested that DNA hypomethylation might affect the structure and dynamics of chromatin regions that are critical for chromosome stability and segregation, thus favouring chromosomal nondisjunction during meiosis. Maternal global DNA hypomethylation has not yet been analyzed as a potential risk factor for chromosome 21 nondisjunction. This study aimed to asses the risk for DS in association with maternal global DNA methylation and the impact of endogenous and exogenous factors that reportedly influence DNA methylation status. Global DNA methylation was analyzed in peripheral blood lymphocytes by quantifying LINE-1 methylation using the MethyLight method. Levels of global DNA methylation were significantly lower among mothers of children with maternally derived trisomy 21 than among control mothers (P = 0.000). The combination of MTHFR C677T genotype and diet significantly influenced global DNA methylation (R² = 4.5%, P = 0.046). The lowest values of global DNA methylation were observed in mothers with MTHFR 677 CT+TT genotype and low dietary folate. Although our findings revealed an association between maternal global DNA hypomethylation and trisomy 21 of maternal origin, further progress and final conclusions regarding the role of global DNA methylation and the occurrence of trisomy 21 are facing major challenges.

The aims of the present study were to assess (1) the parental origin of trisomy 21 and the stage in which nondisjunction occurs and (2) the relationship between altered genetic recombination and maternal age as risk factors for trisomy 21. The study included 102 cases with Down syndrome from the Croatian population. Genotyping analyses were performed by polymerase chain reaction using 11 short tandem repeat markers along chromosome 21q. The vast majority of trisomy 21 was of maternal origin (93%), followed by paternal (5%) and mitotic origin (2%). The frequencies of maternal meiotic I (MI) and meiotic II errors were 86% and 14%, respectively. The highest proportion of cases with zero recombination was observed among those with maternal MI derived trisomy 21. A higher proportion of telomeric exchanges were presented in cases with maternal MI errors and cases with young mothers, although these findings were not statistically significant. The present study is the first report examining parental origin and altered genetic recombination as a risk factor for trisomy 21 in a Croatian population. The results support that trisomy 21 has a universal genetic etiology across different human populations.