Chromosomal abnormalities are deviations in the number or structure of chromosomes and the diseases and anomalies that cause them. There are numerical ones in which there is a change in the number of chromosomes (aneuploidy) and structural ones in which a part of a chromosome is replaced, moved to another place, multiplied or completely lost. The cause of chromosomal abnormalities remains unexplored, but heredity plays a major role in their development. An example of a structural chromosomal anomaly are microdeletion syndromes caused by the deletion of a small part of a chromosome. The mutation can affect different organs and manifest different symptoms and characteristics depending on which genes the deletion encompasses. One example of such a syndrome is the microdeletion syndrome 17q12, a recently discovered and only recently researched syndrome caused by a deletion of the long arm of the 17th chromosome at position 12. In addition to developmental difficulties as one of the main features of microdeletion syndrome 17q12, renal cysts, other renal anomalies, diabetes, pancreatic anomalies are the most common findings in patients. However, the appearance of a very diverse spectrum of symptoms is observed, and the background in the development of certain symptoms is associated with the involvement of more than 15 genes, among which the most important role is played by HNF1ß and LHX1 genes. Although the mutation can be inherited autosomally dominantly, a large number of cases arise de novo, and in both forms, a great variety of phenotypic characteristics is seen among patients, even those who are related. It is precisely this diversity that has proved interesting to physicians who present some completely different cases of 17q12 microdeletion syndrome, that is, how everything can be manifested from person to person. The importance of noticing diversity lies in the importance of monitoring and treating affected patients and the appearance of relatively unknown types of patients. The aim of this review was, therefore, to summarize in one place the possible phenotypic characteristics and their combinations in persons with microdeletion syndrome 17q12.