Chromosomes 165 Genetics 80 Chromosome 41 Biology 27 Cytogenetics 26 Heredity 25 chromosomes 21 CHROMOSOME 20 Mutation 20 Cytology 15 Genes 15 cytogenetics 14 Linkage 13 CHROMOSOMES 12 Chromosome Mapping 12 Gene mapping 12 MUTATION RESEARCH: INTERNATIONAL JOURNAL OF MUTAGENESIS CHROMOSOME BREAKAGE AND RELATED SUBJECTS 12 Evolution 11 Microbiology 11 Viral chromosomes 11 chromosome 11 Cell Division 10 Mendelism 10 Cell division 9 Genomics 9 Mitosis 9 Molecular genetics 9 Nucleotide sequence 9 Sex determination 9 Gene Mutation 8