UMass Boston

Developmental Biology, Genetics

PhD, Genetics, University of Wisconsin Madison
BS, Genetics, University of California Davis

• Bowen, M.E., K. Henke, K.R. Siegfried, M.L. Warman, M.P. Harris (2012). Efficient mapping and cloning of zebrafish mutants by low coverage whole genome sequencing. Genetics, 190(3), 1017-24.
• Liew, W.C., R. Bartfai, Z. Lim, R. Sreenivasan, K.R. Siegfried, L. Orban (2012). The zebrafish has polygenic sex determination. PLOS ONE, 7(4), e34397.
• Saito, K., KR Siegfried, C. Nüsslein-Volhard, N. Sakai (2011). Isolation and cytogenetic characterization of zebrafish meiotic prophase I mutants. Developmental Dynamics, 240, 1779-1792.
• Siegfried, K.R. (2011). Molecular and chromosomal aspects of sex determination. In: Farrell A.P. (ed.) Encyclopedia of Fish Physiology: from genome to environment. Elsevier.
• Siegfried, K.R. (2010). In search of determinants: gene expression during gonadal sex differentiation. Journal of Fish Biology 76, 1879-1902.
• Siegfried, K.R., C. Nüsslein-Volhard (2008). Germ line control of female sex determination in zebrafish. Developmental Biology, 324(2), 277-287.

The Siegfried Lab

Germ Cell Development

The germ line is a unique tissue in that it is the only cell type in the body that contributes to the next generation. The Siegfried Lab uses the zebrafish to study the genetic regulation underlying germ cell development. We have isolated a collection of zebrafish mutants with defects in various aspects of germ cell development. These range from early germ cell survival, meiotic defects, and formation of germ cell tumors. Our ongoing work on these mutant lines has led to the discovery of genes that are relevant to human infertility and reproductive function. Through further analysis of these mutants, we aim to uncover the mechanisms by which these genes function in germ cell development.

Sex Determination

There is a vast diversity of methods by which sex is determined in animals. Despite this, there is a common set of genes that seem to regulate sexual fates within vertebrates. In humans, mutations disrupting these genes can lead to Disorders of Sexual Development (DSD). DSDs can consist of a broad range of defects that may lead to problems with endocrine function, sexual identity, infertility and susceptibility to gonadal cancers. Zebrafish and humans share many common genes that regulate this process. To understand the genetic regulation of sexual development, the Siegfried lab is studying sex-determination and gonadal sex-differentiation in the zebrafish. To this end, we are using both mutant analysis and genomic approaches to identify genes that regulate sexual development in zebrafish.