Robertsonian translocations have been seen involving all combinations of acrocentric chromosomes.
2.
The X chromosome is the largest of the acrocentric chromosomes, and the Y chromosome is medium-sized.
3.
A Robertsonian translocation results when the long arms of two acrocentric chromosomes fuse at the centromere and the two short arms are lost.
4.
In some cases, a metacentric chromosome is formed by balanced translocation : the fusion of two acrocentric chromosomes to form one metacentric chromosome.
5.
In an acrocentric chromosome the p arm contains genetic material including repeated sequences such as nucleolar organizing regions, and can be translocated without significant harm, as in a balanced Robertsonian translocation.
6.
The extant, it is apparent that the evolutionary sequence is a reduction of two acrocentric chromosomes in the great apes to one metacentric chromosome in humans ( see Karyotype # Aneuploidy ).
7.
Mouflon and domestic sheep have 54 chromosomes, with three pairs ( 1 + 3, 2 + 8, 5 + 11 ) of ancestral acrocentric chromosomes joined to form bi-armed chromosomes.
8.
Common Robertsonian translocations are confined to the acrocentric chromosomes 13, 14, 15, 21 and 22, because the short arms of these chromosomes encode for rRNA which is present in multiple copies.
9.
Before the discovery of " Dichroplus silveiraguidoi " in Uruguay in 1956, " Dactylotum bicolor " had the lowest known number of chromosomes among grasshopper species, with seventeen acrocentric chromosomes.
10.
Their children, however, may either be normal and carry the fusion chromosome ( depending which chromosome is represented in the gamete ), or they may inherit a missing or extra long arm of an acrocentric chromosome.
मोबाइल