Surfactant protein A and D gene polymorphisms and protein expression in victims of sudden infant death
Article first published online: 4 NOV 2008
©2008 The Author(s)/Journal Compilation ©2008 Foundation Acta Pædiatrica/Acta Pædiatrica
Volume 98, Issue 1, pages 62–68, January 2009
How to Cite
Stray-Pedersen, A., Vege, Å., Opdal, S. H., Moberg, S. and Rognum, T. O. (2009), Surfactant protein A and D gene polymorphisms and protein expression in victims of sudden infant death. Acta Paediatrica, 98: 62–68. doi: 10.1111/j.1651-2227.2008.01090.x
- Issue published online: 9 DEC 2008
- Article first published online: 4 NOV 2008
- Received 30 July 2008; accepted 22 September 2008.
- Immunohistochemical expression;
- Single nucleotide polymorphism;
- Sudden infant death syndrome;
- Surfactant protein A;
- Surfactant protein D
Aim: To investigate the innate immune components surfactant protein A (SP-A) and D (SP-D) in victims of sudden infant death syndrome (SIDS).
Methods: Ten common single nucleotide polymorphisms (SNPs) in the exons of SP-A1, SP-A2 and SP-D genes were analysed in 42 cases of SIDS and 46 explained sudden infant deaths. SP-A and SP-D protein expression in tissue from the aerodigestive tract was semi-quantitatively evaluated by immunohistochemistry.
Results: SP-D immunoreactivity was found in lungs and tissue from submandibular gland, palatine tonsils and duodenum. Positive SP-A immune staining was found exclusively in lung tissue. Neither the allele nor the haplotype distribution of the SP-A and SP-D genes was significantly different in SIDS compared to explained deaths. The most common SP-A haplotype, 6A2/1A0, tended to be overrepresented in the cases with low immunohistochemical SP-A expression (61%) compared to cases with high expression (49%), p = 0.08. The SP-D expression was not influenced by the 11 C/T or 160 A/G polymorphisms.
Conclusion: No significant association between the common genetic variants of SP-A and SP-D and SIDS is disclosed by the present study. However, low SP-A protein expression may possibly be determined by the 6A2/1A0 SP-A haplotype, this should be subject for further investigation.