The recent article by Vathulya et al titled ‘Role of MSX1 in the development of non-syndromic clefts in the sub-Himalayan region of India’ offers an important contribution to understanding regional genetic influences in non-syndromic cleft lip and/or palate (NSCL/P). The study’s focus on the MSX1 SNPs rs11726039 and rs3821949 in a geographically and genetically distinct Indian cohort fills a critical knowledge gap. However, despite its relevance and regional novelty, several aspects of the methodology and interpretation merit deeper scrutiny.
Firstly, the case-control design and trio analysis are sound, yet the sample size remains a limitation—not merely in power but in stratified statistical inference. For instance, the sole statistically significant result (p = 0.001) for rs3821949 in fathers lacks replication in patients or mothers. Such an isolated finding could be spurious or attributable to stochastic variability rather than true biological association, especially in the absence of significant linkage disequilibrium or consistent protective trends across the trio data. While the authors suggest this could indicate a paternal protective effect, the finding might reflect sampling error without validation.
Secondly, although environmental data were recorded, their integration into the statistical model was minimal. A multifactorial aetiology demands more than token documentation of maternal smoking and folic acid intake. Contemporary approaches utilise logistic regression models incorporating both genetic and environmental covariates to dissect interaction effects, as previously demonstrated in studies of MTHFR and BCL3 polymorphisms. The absence of such multivariable analysis limits the causal inferences that can be drawn.
Additionally, the control group comprised children admitted for elective surgeries, raising concerns about selection bias. Although convenient, this group may differ systematically from the general population in nutritional status or healthcare access—factors known to confound cleft risk studies. Ideally, population-based controls should be employed to reduce this bias.
The authors appropriately acknowledge underreporting of maternal smoking due to sociocultural stigma; however, the broader issue of recall bias in self-reported exposures deserves emphasis. Moreover, since no significant deviation from Hardy-Weinberg equilibrium was noted, it is curious that this aspect wasn’t discussed in relation to the absence of association in the primary outcomes.
In sum, while this study contributes valuable population-specific data to the cleft genetics literature, its statistical and methodological limitations temper the strength of its conclusions. Future investigations should integrate gene-environment interactions robustly and consider epigenetic modifiers—given the developmental plasticity inherent in craniofacial morphogenesis. ,
