Background. There are many known chromosomal abnormalities that may influence intrauterine development and human physiology. Here we have analyzed some of the identified chromosome number and structure aberrations.
Material and methods. 781 abnormal karyotype samples from Medical Genetics Centre at Vilnius University Hospital Santariskiu Klinikos dated 2000-2013 were analyzed. Analysis was done using “Microsoft Excel” and data was compared to the results from other countries.
Results. 62.1% of the analyzed karyotypes had chromosome number abnormalities, trisomy 21 was the most common one (73% of all the chromosome number aberrations). Trisomy 18 was found in 7.5%, trisomy 13 in 1.9%, trisomy 9 in 0.2% and sex chromosome number abnormalities in 20.4% of all the abnormal karyotype samples. Balanced chromosomal aberrations were detected in 15.2%, and reciprocal translocations were the most common among them; whereas deletions were the most frequently identified in the groups of unbalanced aberrations (9.9%). Mosaic karyotypes were found in 10.3%, complex rearrangements in 2.6% of all cases. 415 of the pathologic karyotypes (53%) were identified in females and 366 (47%) in males. Chromosomes 8 (n=8), 5 and 18 (each n=7) were most commonly involved in the chromosomal rearrangements.
Conclusions. During 13 years period there were various chromosome number and structure aberrations identified in the Lithuanian subjects. This analysis shows a detail description of common and rare chromosomal abnormalities. Since there is a vast variety of a chromosomal abnormality, a catalog of chromosomal aberrations is essential for the further analysis of genotype - phenotype data.
