Navigation Links
Chromosome inheritance? Not the same for all the chromosomes

New findings of researchers from the University of Modena and Reggio Emilia (Mauro Mandrioli, Valentina Monti and Gian Carlo Manicardi) show that in aphids the two X chromosomes have a different inheritance. The study was published in Comparative Cytogenetics.

Aphids are insects with a sex determination model based on the presence of two X chromosomes (XX) in females and a single X chromosome (XO) in males. Previous studies suggested that X chromosome loss during male determination was random and that both X chromosomes have the same probability to be inherited in males. On the contrary, some authors suggested the presence of strong biases in the transmission of sex chromosomes, so that X chromosomes may have a non-mendelian inheritance in aphids.

On the basis of the results obtained in potato aphid Macrosiphum euphorbiae, we suggest the presence of a non-random elimination of one X chromosome during the male determination process. In particular, the unequal distribution of ribosomal DNA (rDNA) genes between the two X chromosomes could favour the loss of the X chromosome with fewer rDNA genes. This result is due to the fact that all the aphid eggs during the prophase present two X chromosomes linked by rDNA genes. However, in eggs developing as females, the connection is quickly lost, but in male generating eggs the X chromosomes remain attached by rDNA genes and undergo a sort of non-canonical reductional division, so that at the end of this peculiar division, the egg has one X chromosome only and it is determined as a male.

X chromosomes with few rDNA genes seem to be less sticky that X chromosomes with larger rDNA regions, so that their inheritance is not random and X chromosomes with few rDNA genes may be lost and not inherited in males. Mutations in the chromosome structure could therefore affect chromosomal inheritance even if these changes do not affect regions involved in centromere functioning.


Contact: Mauro Mandrioli
Pensoft Publishers

Related biology news :

1. New thinking on regulation of sex chromosomes in fruit flies
2. The machinery for recombination is part of the chromosome structure
3. How yeast chromosomes avoid the bad breaks
4. Discovering the bigger picture in chromosomes
5. Kinetochores prefer the silent DNA sections of the chromosome
6. Could ovarian stimulation cause an increase in oocyte chromosome abnormalities?
7. New insight into chromosome segregation: Centromere-independent kinetochore assembly
8. Study in roundworm chromosomes may offer new clues to tumor genome development
9. Research into chromosome replication reveals details of heredity dynamics
10. Finger-trap tension stabilizes cells chromosome-separating machinery
11. Chromosome imbalances lead to predictable plant defects
Post Your Comments:
(Date:10/29/2015)... YORK , Oct. 29, 2015 ... technology, announced a partnership with 2XU, a global ... to deliver a smart hat with advanced bio-sensing ... and other athletes to monitor key biometrics to ... the strategic partnership, the two companies will bring together ...
(Date:10/27/2015)... 2015 Synaptics Inc. (NASDAQ: SYNA ), the ... has adopted the Synaptics ® ClearPad ® ... its newest flagship smartphones, the Nexus 5X by LG ... --> --> Synaptics works closely ... collaboration in the joint development of next generation technologies. ...
(Date:10/26/2015)... -- Delta ID Inc., a company focused on bringing secure ... announced its ActiveIRIS® technology powers the iris recognition feature ... NTT DOCOMO, INC in Japan . ... include iris recognition technology, after a very successful introduction ... 2015, world,s first smartphone to have this capability. ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... ... November 25, 2015 , ... Jessica Richman and Zachary Apte, ... their initial angel funding process. Now, they are paying it forward to other ... stage investments in the microbiome space. In this, they join other successful ...
(Date:11/24/2015)... , Nov. 24, 2015 Cepheid (NASDAQ: ... speaking at the following conference, and invited investors to ... NY      Tuesday, December 1, 2015 at 11.00 ... NY      Tuesday, December 1, 2015 at 11.00 ... Conference, New York, NY      Tuesday, ...
(Date:11/24/2015)... ... November 24, 2015 , ... ... But unless it is bound to proteins, copper is also toxic to cells. ... at Worcester Polytechnic Institute (WPI) will conduct a systematic study of copper in ...
(Date:11/24/2015)... Global, Inc., a worldwide provider of clinical research services headquartered in ... company has set a new quarterly earnings record in Q3 of ... for Q3 of 2014 to Q3 of 2015.   ... with the establishment of an Asia-Pacific office ... Kingdom and Mexico , with the ...
Breaking Biology Technology: