16p11.2 microdeletion syndrome: a case report

Background

The recurrent ∼ 600 kb 16p11.2 microdeletion is among the most commonly known genetic etiologies of autism spectrum disorder, overweightness, and related neurodevelopmental disorders.

Case presentation

Our patient is a 2-year-old white girl from the first pregnancy of a non-consanguineous healthy young white couple (father 33-years old and mother 29-years old). Our patient and her parents’ DNA were analyzed by comparative genomic hybridization-array platform. Comparative genomic hybridization-array analysis highlighted a ∼ 600 kb deletion in 16p11.2 region. It has a segregant nature, since it was found in the mother and in her 2-year-old daughter. The microdeletion was confirmed by fluorescence in situ hybridization analysis.

Conclusions

The presented clinical case is worthy of note since the observed microdeletion is often associated with a clinical phenotype tending to overweightness, but the proband (female) was hospitalized due to poor height and weight development, and anorexia. Moreover, the segregant nature of the observed genomic abnormality has to be noted, as well as the phenotypic variability between the mother and daughter. The case described here enriches the phenotypical spectrum linked to the 16p11.2 microdeletion. For these reasons, in the presence of a suspected genetic pathology it is fundamental to study the proband from the clinical point of view, to extend the clinical observation to the parents, and to provide a good family anamnesis. In this way, it is possible to reveal the presence of a familial genetic pathology whose phenotypical outcomes can be highly variable among the members of a family.

Prevention of neural tube defects and maternal gestational diabetes through the inositol supplementation: preliminary results

OBJECTIVE

Our study aims to demonstrate that the use in the preconceptional period until the 24th week of pregnancy of inositol and folic acid, first of all, preserves the product of conception from neural tube defects (NTDs) and then, thanks to inositol supplementation, it possibly counteracts and prevents the onset of maternal gestational diabetes (GDM).

PATIENTS AND METHODS

We have collected data derived from pregnant women arrived at our laboratory, from January 2014 to January 2016, with no family history of type 2 diabetes and hypertension. The first group (n = 68 women) was treated from the preconceptional period until the 24th week of pregnancy with 1.75 g/day myo-inositol, 250 mg/day D-chiro-inositol, 12.5 mg/day Zinc pidolate, 100 mg/day methylsulfonylmethane, 120 mg/day Vitamin C and 400 mcg/day (6S)-5-methyltetrahydrofolic acid. The control group (n = 72) was only treated with 400 mcg/day folic acid. The main outcome measure was the prevalence of maternal GDM. Secondary outcome measures were the prevalence of NTDs and fetal macrosomia.

RESULTS

A significant difference was found regarding body mass index (BMI), fasting oral glucose tolerance test (OGTT), after 1-h-glucose OGTT, 2-h-glucose OGTT, glycated hemoglobin (HbA1c) and serum folate, between the two groups. Five infants, in the control group, weighted greater than 4 kg. Moreover, we found a positive correlation between HbA1c and OGTT at the 24th week of pregnancy.

CONCLUSIONS

This study shows the efficacy of preconceptional supplementation of inositol to reduce the risk of the onset of GDM and to confirm the importance of folic acid supplementation to avoid NTDs development. Moreover, the positive correlation between HbA1c and OGTT may be useful to consider the use of HbA1c as a single tool for GDM prevention and diagnosis in selected woman in pregnancy.