Association between the HHEX polymorphism and delayed memory in first-episode schizophrenic patients

Area of Science:

• Neuroscience
• Genetics
• Psychiatry

Background:

• The hematopoietically-expressed homeobox (HHEX) gene is crucial for immune system regulation and implicated in psychiatric disorders.
• Abnormalities in HHEX have been linked to psychopathology and cognitive deficits.

Purpose of the Study:

• To investigate the association between HHEX rs1111875 polymorphism and schizophrenia susceptibility.
• To examine the impact of this polymorphism on cognitive deficits in first-episode schizophrenia patients (FSP).

Main Methods:

• Cognitive function was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in 239 FSP and 368 healthy controls.
• HHEX rs1111875 polymorphism was genotyped.
• Statistical analyses were performed adjusting for relevant covariates.

Main Results:

• No significant differences in allelic or genotypic frequencies of HHEX rs1111875 were found between FSP and healthy controls.
• FSP exhibited significantly lower cognitive scores across most domains compared to controls, except for visuospatial/constructional ability.
• The HHEX rs1111875 polymorphism was significantly associated with delayed memory performance in FSP, but not in healthy controls.

Conclusions:

• The HHEX rs1111875 polymorphism does not appear to contribute to the susceptibility of developing first-episode schizophrenia.
• This specific polymorphism may influence delayed memory deficits observed in FSP.
• First-episode schizophrenia patients demonstrate widespread cognitive impairments, with notable exceptions in visuospatial/constructional domains.