The minimal deletion causing this syndrome has been defined as a 3 megabase region that contains the genes GPR35, GPC1 and STK25. Almost all deletions are found to be terminal deletions at the end of chromosome 2. There is a high frequency of de novo deletions, but multiple cases within a single family are also observed. Equal proportions of maternally and paternally derived rearrangements were seen in Aldred's series. No common breakpoints for the deletion were identified indicating that the<unk>  rearrangement is unlikely to be mediated by non-homologous recombination and low-copy repeats. In a study of 20 patients, no clear relationship was found between clinical features and the size or position of the monosomic region.
2q37 monosomy
Chromosome 15q partial deletion
Xp11.2 duplication
Tetrasomy 18p
Chromosome 15q trisomy
Distal trisomy 10q
Chromosome 2q deletion
Partial monosomy 13q