Transmission ratio distortion in offspring of mouse heterozygous carriers of a (7.18) Robertsonian translocation.
Transmission ratio distortion (TRD) is defined as a significant departure from expected Mendelian ratios of inheritance of an allele or chromosome. TRD is observed among specific regions of the mouse and human genome and is frequently associated with chromosome rearrangements such as Robertsonian (Rb) chromosomes. We intercrossed mice heterozygous for a (7.18) Rb translocation and genotyped chromosomes 7 and 18 in 1812 individuals, 47% of which were informative for chromosome segregation. We substantiated previous findings that females were less likely than expected to transmit the Rb chromosome to their offspring. Surprisingly, however, we report that heterozygous males transmitted the Rb translocation chromosome significantly more frequently than the acrocentrics. The transmission of the Rb chromosome was not significantly influenced by either the sex of the Rb grandparent or the strain of the Rb.
Underkoffler
Lara A
LA
Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA.
Mitchell
Laura E
LE
Abdulali
Zaki S
ZS
Collins
Joelle N
JN
Oakey
Rebecca J
RJ
D000818:Animals; D020090:Chromosome Segregation; D002875:Chromosomes; D003433:Crosses, Genetic; D005260:Female; D006579:Heterozygote; D007621:Karyotyping; D008297:Male; D008540:Meiosis; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008815:Mice, Inbred Strains; D012727:Sex Characteristics; D012744:Sex Ratio; D014178:Translocation, Genetic