A published Nature article from 1998 is under scrutiny. The journal issued an expression of concern regarding a PCR gel image in Fig. 4a. The image appears in the paper "Editorial Expression of Concern: The X-linked lymphoproliferative-disease gene product SAP regulates signals induced through the co-receptor SLAM."

The concern focuses on lanes B3 and B1 in Fig. 4a. Editors noted a high degree of similarity between the bottom halves of these lanes. The article, published online October 1, 1998, details research on the SAP protein and its role in X-linked lymphoproliferative disease (XLP).

The expression of concern raises questions about the validity of the affected data. This could impact the interpretation of the study's findings. The original research was conducted by scientists at multiple institutions. These include Beth Israel Deaconess Medical Center, Harvard Medical School, and others in Italy and Austria.

XLP is a rare immune deficiency. It leaves individuals vulnerable to severe infections and lymphoma. The SAP protein is crucial for proper immune cell function. Further investigation is needed to determine the extent of the issue. Nature has not yet announced further steps. The scientific community awaits clarification on the implications for XLP research.