The incidence and possible relevance of Y-linked microdeletions

Abstract

Microdeletions linked to deletion intervals 5 and 6 of the Y chromosome have been associated with male factor infertility. Members from at least two gene families lie in the region containing azoospermia factor (AZF), namely YRRM and DAZ. With the advent of intracytoplasmic sperm injection (ICSI), it is possible for men with severe male factor infertility to produce a child.

Crypto Wallet or E-Wallet is a well-known term for all of us and so does its usage and dimension of utility. The wallet software is designed to serve its main purpose of storing digital currencies like Bitcoin, Litecoin, Ethereum with the full control to the owner and also to aid in transactions involving cryptocurrencies as the payment mode or exchange item.  It is in simple, yet appealing terms, “power to the masses”.

How is a digital wallet different from a physical wallet?

Although the basic concepts and the purpose are the same in both, there are certain distinguishable features in the method and options among both.

While in a physical wallet, you store the original currency and exchange it for any transaction, in a digital wallet, you are not storing any money, but the private and public keys which hold the address of the currency. This address represents the value of the currency stored.

You have complete power on the decision to use the currency in your physical wallet, but there is always a centralized authority which ultimately controls the entry, exit, and rotation of this currency. When you store digital currency, you are the sole authority controlling its rotation and sometimes generation, if you are a miner.

You physically hand over a regular currency in exchange for any product or service and there is obviously no continuation of this except on your account books. At the same time, when you buy or sell a digital currency through an exchange such as Ethereum Code, you are actually transferring the ownership of the public and private keys holding the address of the currency units, also known as tokens.

The biggest difference comes probably in terms of security. While your physical wallet is bound to be stolen by any tom, dick and harry and even forms a source of livelihood for a big population, your digital wallet is safe and sound in the virtual world. The third party can access it without a second hurdle. The private key is known only to you and is controlled only by you. The person to whom you intend to exchange the token to can get the ownership only if his public and private keys match with that of your token and with what you feed.

Stability is another factor which goes in favor of a physical wallet. The wallet never loses its relevance and worth unless any major economic policies like demonetization or emergency declaration come in. Cryptocurrency wallet, on the other hand, is subjected to everyday market volatility and legal meltdowns of the governing bodies.

Whatever be the arguments, crypto wallets have a unique virtual charm in them which attracts the reality of many risk-takers.

The genetic consequences of such a procedure have been questioned. This report describes the first study of a population (32 couples) of infertile fathers and their sons born after ICSI. The objectives were firstly to determine the incidence and map location of Y chromosome microdeletions and to compare the frequencies with other population studies involving severe male factor infertility, and secondly to formulate a working hypothesis concerning developmental aetiology of Y chromosome microdeletions. The incidence of microdeletions in the ICSI population was shown to be 9.4% (within the range 9-18% reported for populations of severe male factor infertility patients). Microdeletions in two out of three affected father/son pairs mapped in the region between AZFb and AZFc and the third involved a large microdeletion in AZFb and AZFc. Of three affected father/son pairs, microdeletions were detected in the blood of one infertile propositus father and three babies. Assuming that the gonomes of the ICSI-derived babies are direct reflections of those of their fathers germ lines, it is possible that two of three infertile fathers were mosaic for intact Y and microdeleted Y chromosomes. In such cases, the developmental aetiology of the microdeletion may be due to a de-novo microdeletion arising as a post-zygotic mitotic error in the infertile propositus father, thus producing a mosaic individual who may or may not transmit the deletion to his ICSI-derived sons depending on the extent of primordial germ cell mosaicism. In one of three affected fathers, the microdeletion detected in his blood was also detected in his ICSI-derived son. In this case the de-novo event giving rise to the microdeletion may have occurred due to a post- (or pre-) meiotic error in the germ line of this father’s normally fertile father (i.e. the ICSI-derived baby’s grandfather).

PMID:
9237238
[Indexed for MEDLINE]