Riccardo,

I am not a competent person to answer your question. I am Quaternary paleontogist specialized in mammals, and ancient DNA. Try to ask Z. Szyndar ([email protected]), who is also palaeontologists, but a specialist of fossil snakes.

All the best,

Adam

Hi!

Check for Bkm probe. That was identified by Lalji. His work was on sex determination, first he worked on snakes. If you check his publications certainly you get useful information. 

-Singh L (1972) Evolution of karyotypes in snakes. Chromosoma 38:185

-Singh L, Purdom IF, Jones KW (1976) Satellite DNA and evolution of sex chromosomes. Chromosoma 59:43–62

-Sex- and tissue-specific Bkm (GATA)-binding protein in the germ cells of heterogametic sex.

-Banded krait minor satellite (Bkm) contains sex and species-specific repetitive DNA.

Genome-wide analysis of Bkm sequences (GATA repeats): predominant association with sex chromosomes and potential role in higher order chromatin organization and function

http://bioinformatics.oxfordjournals.org/content/19/6/681.long

Functional Significance of Molecular Organization of Sex Chromosomes

http://www.insa.nic.in/writereaddata/UpLoadedFiles/PINSA/Vol60B_1994_5_Art10.pdf

Sex Chromosome Associated Satellite DNA: Evolution and Conservation

http://aerg.canberra.edu.au/library/sex_general/1980_Singh_etal_sex-chromosome_evolution_conservation.pdf

https://en.wikipedia.org/wiki/Lalji_Singh

Hi!

Up to my knowledge, sex chromosome are accurately known only from "advanced snakes" (Caenophidia). The gene content of the Z chromosome in this group of snakes is homologous to Anolis carolinensis chromosome 6 (ACA6). I believe you could design primers and amplify genes localized in ACA6 as supposed to be Z-linked in advanced snakes. For more information please see:

http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1001643

http://rspb.royalsocietypublishing.org/content/282/1821/20151992

Best regards,

Michail