Microdeletion 2q23.3q24.1: Exploring genotype‐phenotype correlations

Abstract

We report a case of a 13-year-old girl with a 5.4Mb de novo deletion, encompassing bands 2q23.3q24.1, identified by array-comparative genomic hybridization. She presented with minor facial and digital anomalies, mild developmental delay during infancy, and behavioral disorders. Few of the reported cases overlap this deletion and all only partially. We tried to compare the clinical features of the patient with the other cases, even though not all of them were molecularly characterized in detail. Considering the neuropsychiatric involvement of the proband and the clinical descriptions of other similar cases, we attempted to identify the genes more probably involved in neurological development and function in the deleted region, particularly GALNT13, KCNJ3 and NR4A2, which are expressed in neuronal cells.

Possible genes responsible for developmental delay observed in patients with rare 2q23q24 microdeletion syndrome: Literature review and description of an additional patient

“…A larger part of the deleted region identified in this study overlapped with the deletion reported by Milani et al (Fig. 2) (Milani et al 2015). Furthermore, the main clinical feature of language delay was also similar to that observed in two patients (Table 1) (Lybaek et al 2009;Newbury et al 2009).…”

“…Furthermore, the main clinical feature of language delay was also similar to that observed in two patients (Table ) (Lybæk et al ; Newbury et al ). However, the deletion identified in this study extended toward a more distal region, and the developmental delay (DD) observed in the present patient was more severe than that in the patient described by Milani et al (Milani et al ). The language delay observed in the patient described by Milani et al in the infantile period improved later (Milani et al ).…”

“…Here, we describe an additional patient harboring a 2q23.3q24.1 microdeletion, which overlapped with the region deleted in the patient reported by Milani et al (2015) but also extended toward the distal region. This finding adds a new insight into the genotype-phenotype correlation in 2q23q24 microdeletion.…”

“…Milani et al reported a patient with 2q23q24 microdeletion syndrome associated with language delay and behavior abnormalities (Milani et al ). They compared the genetic defect and resulting phenotypes of that patient with those of two other previously reported 2q23q24 microdeletion syndrome patients (Lybæk et al ; Newbury et al ).…”

“…2q23q24 microdeletion syndrome described by Lybæk et al is rare, and there are only a few reported cases (Lybæk et al ). Recently, Milani et al reported a female patient with a 2q23.3q24.1 deletion, who had a normal intelligence quotient (IQ), although her early language development was delayed and some behavioral abnormalities were observed (Milani et al ). They compared the genotypes and phenotypes of the known patients and speculated that some genes in this region might be important in the development of the central nervous system by encoding functionally relevant neuronal proteins.…”