My broad interests involve the evolution of genetic and genomic architecture and how the resulting features affect the evolution of species and populations. My current research focuses on the ciliate Paramecium; like all ciliates, Paramecium cells contain two genomes, a somatic genome housed in the macronucleus and a germline genome in the micronucleus. The macronuclear genome undergoes large-scale, developmentally programmed rearrangements, including removal of repetitive elements and other sequences, chromosomal fragmentation, and whole-genome amplification to ~800X. The recent publication of the macronuclear genome of Paramecium tetraurelia (Aury et al., Nature, 2006) has led to the possibility of conducting genomics analyses in Paramecium.
My current work focuses on studying the consequences of the series of at least four whole-genome duplications that occurred in the Paramecium lineage. The last WGD, in particular, provides a great study subject, as over 50% of the genes present before the duplication remain in two copies. In addition, the recent WGD may have coincided with the species radiation that occurred in the P. aurelia species complex. I am studying the effects of the WGD on the speciation of Paramecium and the molecular and functional divergence of paralogs using comparative genomics, bioinformatics, and molecular biological approaches.
McGrath, CL and LA Katz (2004). Genome diversity in microbial eukaryotes. TRENDS in Ecology and Evolution 19 (1): 32-38.
McGrath, CL, RA Zufall, and LA Katz (2006). Ciliate Genome Evolution in Genomics and Evolution of Microbial Eukaryotes (ed. LA Katz and D Bhattacharya). New York: Oxford University Press.
Zufall, RA, CL McGrath, SV Muse, and LA Katz. (2006). Genome architecture drives protein evolution in ciliates. Molecular Biology and Evolution 23 (9):1681-1687.
Waldman, ID, IR Gizer, JA Fagerness, CL McGrath, and DC Rowe (2006). Is COMT a risk factor for ADHD? Testing for association with multiple markers in a gene-based framework. Behavior Genetics 36 (6): 986-987.
McGrath, CL, RA Zufall, and LA Katz (2007). Variation in macronuclear genome content of three ciliates with extensive chromosomal fragmentation: A preliminary analysis. Journal of Eukaryotic Microbiology 54 (3): 242-246.
Kim, JW, J Biederman, CL McGrath, AE Doyle, E Mick, JA Fagerness, S Purcell, JW Smoller, P Sklar, and SV Faraone (2008). Further evidence of association between two NET single nucleotide polymorphisms with ADHD. Molecular Psychiatry 13 (6): 624-630.
McGrath, CL, SJ Glatt, P Sklar, H Le-Niculescu, R Kuczenski, AE Doyle, J Biederman, E Mick, SV Faraone, AB Niculescu, and MT Tsuang (2009). Evidence for genetic association of RORB with bipolar disorder. BMC Psychiatry 9: 70.
Han, MV, JP Demuth, CL McGrath, C Casola, and MW Hahn (2009). Adaptive evolution of young gene duplicates in mammals. Genome Research 19 (5): 859-867.
McGrath, CL, C Casola, and MW Hahn (2009). Minimal effect of ectopic gene conversion among recent duplicates in four mammalian genomes. Genetics 182 (2): 615-622.