Decrease in the T-box1 gene expression in embryonic brain and adult hippocampus of down syndrome mouse models.

Area of Science:

• Neuroscience
• Genetics
• Developmental Biology

Background:

• Down syndrome (DS, Trisomy 21) is the leading genetic cause of intellectual disability.
• While DS involves delayed fetal brain development, a direct molecular link to intellectual disability remains unclear.

Purpose of the Study:

• To identify differentially expressed molecules in the prenatal forebrain and adult hippocampus of a DS mouse model.
• To investigate the potential role of Tbx1 in connecting developmental and cognitive deficits in DS.

Main Methods:

• Transcriptomic profiling of the hippocampus in adult Ts1Cje mice (a DS model).
• Comparison with existing transcriptomic data from the prenatal forebrain (embryonic day 14.5) of the same mouse model.
• Validation of Tbx1 mRNA expression in additional DS mouse models (Dp(16)1Yey/+ and Ts1Rhr).

Main Results:

• Decreased Tbx1 mRNA expression was observed in the adult hippocampus of Ts1Cje mice.
• This reduced Tbx1 expression was also present in the prenatal forebrain of Ts1Cje mice.
• Diminished Tbx1 mRNA levels were confirmed across different DS mouse models with varying trisomic regions.

Conclusions:

• Tbx1 mRNA expression is consistently reduced in both prenatal and adult stages of DS mouse models.
• These findings propose Tbx1 as a potential molecular link between delayed fetal brain development and intellectual disability in Down syndrome.