14. ULUSAL TIBBİ GENETİK KONGRESİ“Uluslararası Katılımlı”, Ankara, Turkey, 20 - 22 November 2020, pp.77
3q29 microdeletion
syndrome results from a loss of 1.6 Mb at the terminal end of chromosome 3.
Although most cases are de novo, familial cases have also been
reported. The prevalence of the syndrome is 1: 30,000-1: 40,000. The most common findings are
learning problems, speech delay, a high nasal bridge and ocular abnormalities.
There is also a 40-fold increased risk for schizophrenia. Our 17-year-old
female patient was born from unrelated parents; there was no history of a
similar disease in the family. Genetic testing was performed because of
psychosis, mild dysmorphic facial appearance and mental retardation. CGH Array analysis of the
patient revealed a deletion on chr3: 195,762,817-197,356,334 and a duplication
on chr3: 197,386,179-197,851,986. To our knowledge, the phenotype of
the patient may be due to nonallelic homologous recombination (NAHR). NAHR explains the
unity of deletion and duplication in juxtaposed regions. The number of cases
reported in the literature is limited, which made us think that patients could
not be diagnosed due to subtle dysmorphic findings. Therefore, we
aimed to emphasize that microdeletion syndromes should be kept in mind for the patients who have
mild dysmorphic findings and early-onset psychiatric diseases. Keywords: 3q29, microdeletion