### XKRX Gene Overview

**Gene Symbol**: XKRX  
**Description**: The XKRX gene encodes a protein that is part of the XK/Kell complex, which is significant in the Kell blood group system. This protein features several transmembrane domains and is likely a membrane transporter located at the cell surface. It is predominantly expressed in the placenta, particularly in syncytiotrophoblasts, with moderate expression in the adrenal gland, low levels in the trachea, and very low levels in the bone marrow.

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### Additional Information:

1. **Associated Genes**:
   - Genes in the XK/Kell blood group system: XKA, and XKB, which are known to be related to the XK glycoprotein.
   - Genes involved in placenta development and function, although specific associations beyond the Kell blood group complex are limited in the literature.

2. **Aging and Age-Related Diseases**:
   - There is limited direct information specifically linking XKRX to aging or age-related diseases in current research.
   - Some studies suggest that expression profiles in placental genes may influence maternal-fetal interactions during pregnancy, which could indirectly relate to conditions observed in aging, like hypertension or diabetes during pregnancy.
   - Any potential association or functional impact on age-related disease remains largely speculative, requiring more targeted studies in this domain.

3. **Drug Interactions**:
   - There are no well-documented drugs or drug classes directly known to interact with the XKRX gene or the protein product based on current literature.
   - However, transporters such as the one encoded by XKRX may have indirect implications in pharmacokinetics, particularly in fetal drug exposure during pregnancy due to its placenta expression.

4. **Pathways and Biological Processes**:
   - **Cellular Processes**: Given its role as a transporter, XKRX may be involved in membrane transport processes that are critical during placental nutrient transport.
   - **Developmental Pathways**: It likely contributes to processes related to placentation and fetal development, given its expression pattern.
   - **Immunological Functions**: As a member of the XK/Kell complex, it may be implicated in immune responses related to blood group antigen expression.

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### Conclusion

The XKRX gene is crucial in its specialized role within the placenta and potentially in the Kell blood group system. Despite its significance, information directly linking this gene to aging, pharmacological interactions, or broader biological pathways remains limited and warrants further research.